Journal articles: 'Olefin reactions'

1

Liu, Qiang, Xufang Liu, and Bin Li. "Base-Metal-Catalyzed Olefin Isomerization Reactions." Synthesis 51, no. 06 (February 19, 2019): 1293–310. http://dx.doi.org/10.1055/s-0037-1612014.

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The catalytic olefin isomerization reaction is a highly efficient and atom-economic transformation in organic synthesis that has attracted tremendous attention both in academia and industry. Recently, the development of Earth-abundant metal catalysts has received growing interest owing to their wide availability, sustainability, and environmentally benign nature, as well as the unique properties of non-precious metals. This review provides an overview of a broad range of base-metal-catalyzed olefin isomerization reactions categorized according to their different reaction mechanisms.1 Introduction2 Base-Metal-Catalyzed Olefin Isomerization Reactions3 Base-Metal-Catalyzed Cycloisomerization Reactions4 Conclusion

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Chow, Yuan L., and Xianen Cheng. "The dual pathway in photocycloaddition of 1,3-diketonatoboron difluorides: excimer reactions." Canadian Journal of Chemistry 69, no. 10 (October 1, 1991): 1575–83. http://dx.doi.org/10.1139/v91-232.

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The lowest singlet excited state of dibenzoylmethanatoboron difluoride DBMBF2, a model compound of the BF2 complexes of 1,3-diketones, reacted with various simple olefins to give regiospecific and stereospecific photocycloadducts of 1,5-diketones similar to those from the de Mayo type reaction. DBMBF2 in acetonitrile exhibited two discrete fluorescences at 398 and 416 nm for the monomer and at 522 nm for the excimer; they were both quenched, but in different proportions, by a simple olefin. An "oxygen test" showed that the excimer of DBMBF2 is formed irreversibly in acetonitrile. The quantum yields of the photocycloaddition were shown to be proportional not only to olefin concentrations but also to DBMBF2 concentrations. Kinetic analysis has established that the total quantum yield is the sum of those arising from the interactions of the singlet excited DBMBF2 and its excimer, respectively, with an olefin, i.e., the sum of the quantum yields of exciplex and triplex pathways. The contributions from the two pathways are determined by the type of olefins and the range of DBMBF2 concentrations. For endocyclic olefins, the triplex pathway is more important and the corresponding photocycloaddition becomes very efficient as soon as the excimer starts to form in [DBMBF2] > 0.001 M. For the monosubstituted olefins, on the contrary, the exciplex pathway is always more important than the triplex pathway; they react primarily from the singlet excited state of DBMBF2. Key words: singlet state photocycloaddition, irreversible excimer formation, excimer cycloaddition, triplex and exciplex reactions.

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Vosloo, H. C. M., and J. A. K. Du Plessis. "A review of the mechanisms of the olefin metathesis reaction." Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie 7, no. 4 (March 17, 1988): 154–61. http://dx.doi.org/10.4102/satnt.v7i4.921.

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During the olefin metathesis reaction carbon-carbon double bonds are broken and rearranged to give a redistribution of alkilydene groups. A review of the different mechanistic approaches is given under the headings: The pairwise mechanism; The metal carbene chain mechanism with reference to the formation of the carbene and metallacyclobutane intermediate; The reactions of the olefins; and The degradation of unsaturated polymers.

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Křeček, Václav, Jiří Protiva, Miloš Buděšínský, Eva Klinotová, and Alois Vystrčil. "Preparation of C(18)-empiric 20,29,30-trinorlupane derivatives. 1H, 13C NMR and mass spectra." Collection of Czechoslovak Chemical Communications 51, no. 3 (1986): 621–35. http://dx.doi.org/10.1135/cccc19860621.

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Reaction of amide I with nitrous acid gave the olefins II, III and IV. On allylic oxidation of olefin IV α,β-unsaturated ketone V is formed from which olefins VIII and IX were prepared by a sequence of further reactions. Addition of hydrogen to the double bond of olefin IV and α,β-unsaturated ketone V takes place on catalytic hydrogenation from the β-side and leads to derivatives with cis-annellated rings D/E. This made the preparation of hydrocarbons VI and VII epimeric on C(18) possible, which represent reference compounds for the study of the effect of substituents on the chemical shifts of the methyl groups and the saturated carbon atoms of 18αH and 18βH-lupane derivatives. The configuration of the hydroxyl group in epimers XI and XII were derived from 1H NMR spectra. Deuteration of olefins III, IV and IX gave deuteriohydrocarbons XVI to XVIII. The 1H, 13C NMR and mass spectra of the substances prepared are discussed.

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Silva, Thiago S., and Fernando Coelho. "Methodologies for the synthesis of quaternary carbon centers via hydroalkylation of unactivated olefins: twenty years of advances." Beilstein Journal of Organic Chemistry 17 (July 7, 2021): 1565–90. http://dx.doi.org/10.3762/bjoc.17.112.

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Olefin double-bond functionalization has been established as an excellent strategy for the construction of elaborate molecules. In particular, the hydroalkylation of olefins represents a straightforward strategy for the synthesis of new C(sp3)–C(sp3) bonds, with concomitant formation of challenging quaternary carbon centers. In the last 20 years, numerous hydroalkylation methodologies have emerged that have explored the diverse reactivity patterns of the olefin double bond. This review presents examples of olefins acting as electrophilic partners when coordinated with electrophilic transition-metal complexes or, in more recent approaches, when used as precursors of nucleophilic radical species in metal hydride hydrogen atom transfer reactions. This unique reactivity, combined with the wide availability of olefins as starting materials and the success reported in the construction of all-carbon C(sp3) quaternary centers, makes hydroalkylation reactions an ideal platform for the synthesis of molecules with increased molecular complexity.

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Plessow, Philipp N., and Felix Studt. "Olefin methylation and cracking reactions in H-SSZ-13 investigated with ab initio and DFT calculations." Catalysis Science & Technology 8, no. 17 (2018): 4420–29. http://dx.doi.org/10.1039/c8cy01194j.

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The olefin cycle of the methanol-to-olefins process is investigated for the zeolite H-SSZ-13 using periodic, van-der-Waals corrected DFT calculations, together with MP2 corrections derived from cluster models, which are essential for accurate barriers.

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Groso, Emilia, and Corinna Schindler. "Recent Advances in the Application of Ring-Closing Metathesis for the Synthesis of Unsaturated Nitrogen Heterocycles." Synthesis 51, no. 05 (February 8, 2019): 1100–1114. http://dx.doi.org/10.1055/s-0037-1611651.

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This short review summarizes recent advances relating to the application of ring-closing olefin-olefin and carbonyl-olefin metathesis reactions towards the synthesis of unsaturated five- and six-membered nitrogen heterocycles. These developments include catalyst modifications and reaction designs that will enable access to more complex nitrogen heterocycles.1 Introduction2 Expansion of Ring-Closing Metathesis Methods3 Evaluation of Catalyst Design4 Indenylidene Catalysts5 Unsymmetrical N-Heterocyclic Carbene Ligands6 Carbonyl-Olefin Metathesis7 Conclusions

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Cory, Robert M., Paul C. Anderson, Murray D. Bailey, Fred R. McLaren, Richard M. Renneboog, and Brian R. Yamamoto. "Nitro-olefin bicycloannulation: one-step synthesis of tricyclo[3.2.1.02,7]octan-6-ones from cyclohexenones and of tricyclo[2.2.1.02,6]heptan-3-ones from cyclopentenones." Canadian Journal of Chemistry 63, no. 10 (October 1, 1985): 2618–27. http://dx.doi.org/10.1139/v85-435.

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Nitro-olefins bicycloannulate the α′-enolates of α-cyclohexenones and α-cyclopentenones by initial addition at −78 °C, followed by further reaction insitu in the presence of hexamethylphosphoramide in refluxing tetrahydrofuran to give tricyclo[3.2.1.02,7]octan-6-ones and tricyclo[2.2.1.02,6]heptan-3-ones in a single synthetic step. The reactions with 1-nitropropene and with a nitro-olefin having a more complex β-substituent are stereoselective, forming predominantly the tricyclic diastereomer in which the group derived from the β-substituent of the nitro-olefin is syn to the carbonyl bridge. Based on the isolation of intermediates and side products, the mechanism of the bicycloannulation is shown to proceed via sequential kinetically controlled conjugate addition of the enolate to the nitro-olefin at low temperatures, thermodynamically controlled intramolecular Michael addition at higher temperatures to give a bicyclo[2.2.2]octanone intermediate, and hexamethylphosphoramide-assisted expulsion of the nitro group as nitrite ion with formation of the cyclopropane ring. For the first time this type of bicycloannulation has been applied to cyclopentenones, and a one-step synthesis of tricyclenone has been carried out to demonstrate the synthetic utility of this new reaction.

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9

Riehl, Paul S., Daniel J. Nasrallah, and Corinna S. Schindler. "Catalytic, transannular carbonyl-olefin metathesis reactions." Chemical Science 10, no. 44 (2019): 10267–74. http://dx.doi.org/10.1039/c9sc03716k.

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Transannular carbonyl-olefin metathesis reactions complement existing procedures for related ring-closing, ring-opening, and intermolecular carbonyl-olefin metathesis. This enables molecular editing of steroid-derived frameworks.

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10

Remete, Attila Márió, Tamás T. Novák, Melinda Nonn, Matti Haukka, Ferenc Fülöp, and Loránd Kiss. "Synthesis of novel fluorinated building blocks via halofluorination and related reactions." Beilstein Journal of Organic Chemistry 16 (October 16, 2020): 2562–75. http://dx.doi.org/10.3762/bjoc.16.208.

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A study exploring halofluorination and fluoroselenation of some cyclic olefins, such as diesters, imides, and lactams with varied functionalization patterns and different structural architectures is described. The synthetic methodologies were based on electrophilic activation through halonium ions of the ring olefin bonds, followed by nucleophilic fluorination with Deoxo-Fluor®. The fluorine-containing products thus obtained were subjected to elimination reactions, yielding various fluorine-containing small-molecular entities.

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11

Iuliis, Marco Zimmer De, Iain DG Watson, Andrei K. Yudin, and Robert H. Morris. "A DFT investigation into the origin of regioselectivity in palladium-catalyzed allylic amination." Canadian Journal of Chemistry 87, no. 1 (January 1, 2009): 54–62. http://dx.doi.org/10.1139/v08-078.

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The addition of amines or aziridines to prenylacetate is catalyzed by palladium phosphine complexes. The first-formed products have recently been shown to be the branched olefins R2NCMe2CH=CH2, R = alkyl, or R2 = 1,2-C6H10, for example. DFT calculations using the MPW1K functional were performed on reactions of the suspected intermediate η3-prenyl complex [Pd(η3-Me2CCHCH2)(PH3)2]+ with dimethylamine and ethylene imine. The activation barrier for the nucleophilic attack by the amine or the aziridine is calculated to be similar for either the sterically hindered site of the π-allyl ligand to produce the branched olefin complex or the unhindered site to give the linear olefin complex. Therefore, these calculations do not reveal the experimentally observed preference for attack. This observation, along with the experimental observation of lack of isomerization of the branched olefin product of the aziridine reactions, appears to rule out the intermediacy of a π-allyl complex [Pd(η3-Me2CCHCH2)L2]+, L = phosphine or L2 = diphosphine in the C–N bond-forming reaction.Key words: allyl palladium, amine, aziridine, DFT, mechanism, catalysis.

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12

Yahyazadeh, Arash, Ajay K. Dalai, Wenping Ma, and Lifeng Zhang. "Fischer–Tropsch Synthesis for Light Olefins from Syngas: A Review of Catalyst Development." Reactions 2, no. 3 (July 21, 2021): 227–57. http://dx.doi.org/10.3390/reactions2030015.

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Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis. The effects of metals, promoters and supports as the most influential parameters on the catalytic performance of catalysts are discussed meticulously. Fe and Co as the main active metals in FT catalysts are investigated in terms of pore size, crystal size, and crystal phase for obtaining desirable light olefin selectivity. Larger pore size of Fe-based catalysts is suggested to increase olefin selectivity via suppressing 1-olefin readsorption and secondary reactions. Iron carbide as the most probable phase of Fe-based catalysts is proposed for light olefin generation via FTS. Smaller crystal size of Co active metal leads to higher olefin selectivity. Hexagonal close-packed (HCP) structure of Co has higher FTS activity than face-centered cubic (FCC) structure. Transition from Co to Co3C is mainly proposed for formation of light olefins over Co-based catalysts. Moreover, various catalysts’ deactivation routes are reviewed. Additionally, techno-economic assessment of FTS plants in terms of different costs including capital expenditure and minimum fuel selling price are presented based on the most recent literature. Finally, the potential for global environmental impacts associated with FTS plants including atmospheric and toxicological impacts is considered via lifecycle assessment (LCA).

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13

Reany, Ofer, and N. Gabriel Lemcoff. "Light guided chemoselective olefin metathesis reactions." Pure and Applied Chemistry 89, no. 6 (June 27, 2017): 829–40. http://dx.doi.org/10.1515/pac-2016-1221.

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AbstractAn appealing concept in synthetic chemistry is photo-induced catalysis; where dormant complexes become catalytically active upon activation with light. The ruthenium-based olefin metathesis complexes founded on the original Grubbs catalyst have probably been one of the most widely studied families of catalysts for the past 25 years. Greater stability and versatility of these olefin-metathesis catalysts has been achieved by careful design of the ligand sphere, including latent catalysts which are activated by external stimuli. This article describes our recent developments towards light-induced olefin metathesis reactions based on photoactive sulfur-chelated ruthenium benzylidene catalysts. Alternative chemical reactions, be it photo-induced olefin metathesis or other direct photochemical processes, by using light of different frequencies were studied in chemoselective chromatic orthogonal pathways. The lessons learned during the development of these reactions have given birth to selective photo-deprotection sequences and novel pathways for stereolithographic applications.

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14

Klinot, Jiří, Jiří Liška, Alena Forgáčová, Miloš Buděšínský, Jiří Protiva, Stanislav Hilgard, and Alois Vystrčil. "Acid-catalyzed rearrangements of an A(1)-nor-triterpenoid 2α,3α-epoxide." Collection of Czechoslovak Chemical Communications 54, no. 2 (1989): 413–29. http://dx.doi.org/10.1135/cccc19890413.

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Reactions of 2α,3α-epoxide X, derived from 19β,28-epoxy-A(1)-nor-18α-oleanane, with acids proceed with migration of the 10β-methyl group into the position 2β, giving rise to unsaturated alcohols XII and XIV and diene IX. Reaction with boron trifluoride etherate afforded ketone XI in addition to XII and XIV. Olefin VIII rearranged in acidic medium to give olefins XXVI and XXVII. The rearranged products were converted into other derivatives and their structure was established by 1H and 13C NMR, IR, UV and mass spectra.

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Lemcoff, N., and Or Eivgi. "Turning the Light On: Recent Developments in Photoinduced Olefin Metathesis." Synthesis 50, no. 01 (September 21, 2017): 49–63. http://dx.doi.org/10.1055/s-0036-1589113.

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Olefin metathesis is one of the most important methods to form carbon–carbon double bonds and has found many applications in industry and academia. The ability to initiate the reaction using external stimulus such as light, with high spatial and temporal resolution is highly advantageous and provides creative novel opportunities in organic syntheses and material sciences. This review article covers recent advances in light-activated olefin metathesis reactions from the development of novel complexes that can be initiated photochemically to recently reported applications of photoinduced olefin metathesis, as well as the bright newly emerging field of photoredox-mediated metal-free ROMP.1 Introduction2 Light-Activated Olefin Metathesis Complexes2.1 Sulfur-Chelated Hoveyda–Grubbs-Type Complexes2.2 Nitrogen-Chelated Hoveyda–Grubbs-Type Complexes2.3 Catalyst Activation with Photoacid Generators2.4 Phototuning of Active Complexes2.5 Photoactivation of Non-Grubbs-Type Olefin Metathesis Complexes3 Photoredox-Mediated Metal-Free ROMP4 Applications of Photoinduced Olefin Metathesis4.1 Chromatic Orthogonal Olefin Metathesis4.2 UV-Filter-Assisted Olefin Metathesis4.3 Photolithographic Olefin Metathesis Polymerization5 Conclusions

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Zhang, Xiaoqiao, Jianhong Gong, Xiaoli Wei, and Lingtao Liu. "Increased Light Olefin Production by Sequential Dehydrogenation and Cracking Reactions." Catalysts 12, no. 11 (November 17, 2022): 1457. http://dx.doi.org/10.3390/catal12111457.

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In this study, a sequential reaction using selected metal oxides, followed by ZSM-5-based catalysts, was employed to demonstrate a promising route for enhancing light olefin production in the catalytic cracking of naphtha. The rationale for the reaction is based on the induction of alkenes into hydrocarbon feeds prior to cracking. The optimum olefin induction was achieved by carefully optimizing the dehydrogenation active sites Mo/Al2O3 catalyst. The formed alkenes have a lower activation energy for C-H/C-C bond breaking compared to alkanes. This could accelerate the formation of carbenium ions, thus promoting the conversion of n-octane to produce light olefins. Detailed product distribution and DFT calculation indicated a remarkable increase in ethylene and propylene production in the final product through a modified reaction pathway. Compared with the common metal-promoted zeolite catalysts, the new route could avoid the block of zeolite channels and corresponding decreased catalytic cracking activity. The feasibility of the proposed route was confirmed with different ratios of dehydrogenation catalyst to the reactant. The highest yields of ethylene and propylene reached 13.22% and 33.12% with ratios of Mo/Al2O3 and ZSM-5-based catalyst to n-octane both 10:1 at 600 °C. Stability tests showed that the catalytic activity of the double-bed system was stable over 10 cycles.

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Matsuo, Takashi. "Functionalization of Ruthenium Olefin-Metathesis Catalysts for Interdisciplinary Studies in Chemistry and Biology." Catalysts 11, no. 3 (March 10, 2021): 359. http://dx.doi.org/10.3390/catal11030359.

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Hoveyda–Grubbs-type complexes, ruthenium catalysts for olefin metathesis, have gained increased interest as a research target in the interdisciplinary research fields of chemistry and biology because of their high functional group selectivity in olefin metathesis reactions and stabilities in aqueous media. This review article introduces the application of designed Hoveyda–Grubbs-type complexes for bio-relevant studies including the construction of hybrid olefin metathesis biocatalysts and the development of in-vivo olefin metathesis reactions. As a noticeable issue in the employment of Hoveyda–Grubbs-type complexes in aqueous media, the influence of water on the catalytic activities of the complexes and strategies to overcome the problems resulting from the water effects are also discussed. In connection to the structural effects of protein structures on the reactivities of Hoveyda–Grubbs-type complexes included in the protein, the regulation of metathesis activities through second-coordination sphere effect is presented, demonstrating that the reactivities of Hoveyda–Grubbs-type complexes are controllable by the structural modification of the complexes at outer-sphere parts. Finally, as a new-type reaction based on the ruthenium-olefin specific interaction, a recent finding on the ruthenium complex transfer reaction between Hoveyda–Grubbs-type complexes and biomolecules is introduced.

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Oss, Giulia, and Thanh Vinh Nguyen. "Iodonium-Catalyzed Carbonyl–Olefin Metathesis Reactions." Synlett 30, no. 17 (October 2019): 1966–70. http://dx.doi.org/10.1055/s-0039-1690297.

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The carbonyl–olefin metathesis reaction has become increasingly important in organic synthesis due to its versatility in functional group interconversion chemistry. Recent developments in the field have identified a number of transition-metal and organic Lewis acids as effective catalysts for this reaction. Herein, we report the use of simple organic compounds such as N-iodosuccinimide or iodine monochloride to catalyze the carbonyl–olefin metathesis process under mild reaction conditions. This work broadens the scope of this chemical transformation to include iodonium sources as simple and practical catalysts.

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Tran, Uyen P. N., Giulia Oss, Domenic P. Pace, Junming Ho, and Thanh V. Nguyen. "Tropylium-promoted carbonyl–olefin metathesis reactions." Chemical Science 9, no. 23 (2018): 5145–51. http://dx.doi.org/10.1039/c8sc00907d.

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Abera Tsedalu, Atitegeb. "A Review on Olefin Metathesis Reactions as a Green Method for the Synthesis of Organic Compounds." Journal of Chemistry 2021 (September 4, 2021): 1–14. http://dx.doi.org/10.1155/2021/3590613.

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Olefin metathesis is a metal-mediated C-C bond exchange by which the two fragments within the olefin precursor are redistributed as a result of breaking the double bond to obtain a new product. Currently, most of the synthetic organic compounds, polymers, drugs, plastics, and other synthetic materials are synthesized via the application of olefin metathesis reactions. In this review, different types of olefin metathesis reactions with their plausible mechanisms and their application in synthetic organic chemistry have been discussed.

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Liu, Wenqi, Sifan Cheng, Haripal Singh Malhi, Xinhua Gao, Zhenzhou Zhang, and Weifeng Tu. "Hydrogenation of CO2 to Olefins over Iron-Based Catalysts: A Review." Catalysts 12, no. 11 (November 14, 2022): 1432. http://dx.doi.org/10.3390/catal12111432.

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The widespread use of fossil fuels has caused high CO2 concentrations in the atmosphere, which have had a great impact on climate and the environment. Methods for efficiently utilizing CO2 to produce high value-added chemicals have received increasing attention. Among the products of CO2 hydrogenation, olefins, an important petrochemical feedstock, are one of the essential target products. Therefore, CO2 hydrogenation to olefins has been extensively studied, especially for the development of high-performance catalysts. Iron-based catalysts, which are widely used in Fischer–Tropsch synthesis reactions, have also been considered attractive for use in the CO2 hydrogenation to olefins due to their excellent performance in catalytic activity and reaction stability. Most studies have focused on the modulation of morphology; reduction and adsorption properties by tuning the methods of catalyst syntheses; pretreatment conditions and the composition of catalysts, in order to improve hydrogenation activity and olefin yield. In this review, we briefly discuss a thermodynamic overview of the CO2 hydrogenation to olefins reaction, the optimization of catalyst modifications, and current insights into the reaction mechanism; moreover, we summarize current challenges and future trends in the CO2 hydrogenation to olefins.

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Shin, Seunghoon. "The effect of acceptor-substituted alkynes in gold-catalyzed intermolecular reactions." Pure and Applied Chemistry 86, no. 3 (March 20, 2014): 373–79. http://dx.doi.org/10.1515/pac-2014-5039.

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Abstract Alkynes substituted with electron-withdrawing groups participated in various intermolecular reactions with olefin substrates, including [4 + 2] annulation of propiolic acids, intermolecular metathesis-type reaction and carboalkoxylation involving allylethers.

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Fukusumi, Takanori, Natsuki Takei, Yubi Tateno, Takuya Aoki, Ai Ando, Kouhei Kozakai, Hiroko Shima, et al. "Ene-thiol reaction of C3-vinylated chlorophyll derivatives in the presence of oxygen: synthesis of C3-formyl-chlorins under mild conditions." Journal of Porphyrins and Phthalocyanines 17, no. 12 (December 2013): 1188–95. http://dx.doi.org/10.1142/s1088424613500983.

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Reactions of thiol with the C 3-vinyl group of various chlorophyll (Chl) derivatives were examined. The reactions resemble thiol-olefin co-oxidation, except that the vinyl C = C double bond was cleaved to afford a formyl group without any transition metal catalyst, and that the simple anti-Markovnikov adduct of thiol to olefin was obtained as a minor product. Peripheral substituents of Chl derivatives little affected the reaction, while the central metal atom of the chlorin macrocycle influenced the composition of the products. Oxygen and acid dissolved in the reaction mixture can facilitate the oxidation. Sufficiently mild conditions in this regioselective oxidation at the C 31-position are significant in bioorganic chemistry.

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Dugkhuntod, Pannida, and Chularat Wattanakit. "A Comprehensive Review of the Applications of Hierarchical Zeolite Nanosheets and Nanoparticle Assemblies in Light Olefin Production." Catalysts 10, no. 2 (February 18, 2020): 245. http://dx.doi.org/10.3390/catal10020245.

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Light olefins including ethylene, propylene and butylene are important building blocks in petrochemical industries to produce various chemicals such as polyethylene, polypropylene, ethylene oxide and cumene. Traditionally, light olefins are produced via a steam cracking process operated at an extremely high temperature. The catalytic conversion, in which zeolites have been widely used, is an alternative pathway using a lower temperature. However, conventional zeolites, composed of a pure microporous structure, restrict the diffusion of large molecules into the framework, resulting in coke formation and further side reactions. To overcome these problems, hierarchical zeolites composed of additional mesoporous and/or macroporous structures have been widely researched over the past decade. In this review, the recent development of hierarchical zeolite nanosheets and nanoparticle assemblies together with opening up their applications in various light olefin productions such as catalytic cracking, ethanol dehydration to ethylene, methanol to olefins (MTO) and other reactions will be presented.

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Opoku, Ernest, Richard Tia, and Evans Adei. "[3 + 2] versus [2 + 2] Addition: A Density Functional Theory Study on the Mechanistic Aspects of Transition Metal-Assisted Formation of 1,2-Dinitrosoalkanes." Journal of Chemistry 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/4538696.

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The pathways for the transition metal-assisted formation of 1,2-dinitrosoalkane complexes of cobalt and its congeners, have been studied using DFT/M06 with theLACVP*basis set. The activation barriers for the one-step [3 + 2] addition pathway for the formation of 1,2-dinitrosoalkanes, proposed by Bergman and Becker, are generally low compared to the activation barriers for the [2 + 2] addition to form an intermediate, which is the first of the two-step pathway proposed by Rappé and Upton, which are very high. The barriers of the rearrangement of the Rappé intermediates to the final products by reductive elimination involving the second metal-nitrogenπ-bond are also very high. The reactions of the Co complexes have lower activation barriers than Rh and Ir complexes. The barriers of the reactions involving olefins with electron-donating groups are generally lower compared to the reactions of the parent (unsubstituted) ethylene while the activation barriers for reactions of olefins with electron-withdrawing groups are generally higher compared to the parent (unsubstituted) ethylene. The one-step [3 + 2] pathway remains the most favoured irrespective of the metal centre or the nature of the olefin. The mechanism of the reaction is therefore settled in favour of the [3 + 2] addition pathway.

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Li, Yuqi, Upal Kusari, Patrick J. Carroll, Mark G. Bradley, and Larry G. Sneddon. "Polyborane reactions in ionic liquids." Pure and Applied Chemistry 78, no. 7 (January 1, 2006): 1349–55. http://dx.doi.org/10.1351/pac200678071349.

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In contrast to reactions that have been observed in traditional organic solvents, decaborane olefin-hydroboration and alkyne-insertion reactions proceed in ionic liquid (IL) solvents without the need of a catalyst. These reactions now provide important new, high-yield synthetic pathways to functionalized decaborane and ortho-carborane clusters. As illustrated by the synthesis of n-B18H22, ILs can also provide an inert reaction medium for carrying out dehydrocondensation reactions leading to higher fused cage compounds.

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Wright, Dennis L. "Application of Olefin Metathesis to Organic Synthesis." Current Organic Chemistry 3, no. 3 (May 1999): 211–40. http://dx.doi.org/10.2174/1385272803666220202192919.

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Abstract: The design and execution of complex molecule synthesis centers upon those reactions that are truly versatile and reliable, especially those that form carbon-carbon bonds. For many decades, alkene metathesis reactions have found great application in polymer synthesis, but it has only been recently that this reaction is finding a place in the arsenal of the synthetic chemist. This new role for the olefin metathesis reaction is directly related to the recent development of stable, well-defined catalysts for this reaction. Ruthenium and molybdenum catalysts, among others, are finding wide spread use in organic synthesis. These catalysts are able to promote the exchange of two independent alkenes and result in the formation of a new olefin. The most common use for this reaction involves an intermolecular variation whereby a tethered diene is metathesized to form a cycloalkene. This ring-closing metathesis (RCM) process has been shown to be remarkably versatile and is tolerant to a wide range of accompanying functionality. RCM reactions are now widely used for the preparation of carbocyclic, azacyclic, and oxacyclic systems. This review focuses on the versatility offered by these well-defined catalyst systems and focuses on their use in the synthesis of natural and non-natural products.

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Das, Aniruddha, Soumen Sarkar, Baitan Chakraborty, Abhishek Kar, and Umasish Jana. "Catalytic Alkyne/Alkene-Carbonyl Metathesis: Towards the Development of Green Organic Synthesis." Current Green Chemistry 7, no. 1 (May 15, 2020): 5–39. http://dx.doi.org/10.2174/2213346106666191105144019.

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The construction of carbon-carbon bond through the metathesis reactions between carbonyls and olefins or alkynes has attracted significant interest in organic chemistry due to its high atomeconomy and efficiency. In this regard, carbonyl–alkyne metathesis is well developed and widely used in organic synthesis for the atom-efficient construction of various carbocycles and heterocycles in the presence of catalytic Lewis acids or Brønsted acids. On the other hand, alkene-carbonyl metathesis is recently developed and has been a topic of great importance in the field of organic chemistry because they possess attractive qualities involving metal-mediated, metal-free intramolecular, photochemical, Lewis acid-mediated ring-closing metathesis, ring-opening metathesis and cross-metathesis. This review covers most of the strategies of carbonyl–alkyne and carbonyl–olefin metathesis reactions in the synthesis of complex molecules, natural products and pharmaceuticals as well as provides an overview of exploration of the metathesis reactions with high atom-economy as well as environmentally and ecologically benign reaction conditions.

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29

Schindler, Corinna, and Jacob Ludwig. "Lewis Acid Catalyzed Carbonyl–Olefin Metathesis." Synlett 28, no. 13 (May 16, 2017): 1501–9. http://dx.doi.org/10.1055/s-0036-1588827.

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Olefin–olefin metathesis has led to important advances in diverse fields of research, including synthetic chemistry, materials science, and chemical biology. The corresponding carbonyl–olefin metathesis also enables direct carbon–carbon bond formation from readily available precursors, however, currently available synthetic procedures are significantly less advanced. This Synpacts article provides an overview of recent achievements in the field of Lewis acid mediated and Lewis acid catalyzed carbonyl–olefin metathesis reactions.1 Lewis Acid Mediated Carbonyl–Olefin Metathesis2 Lewis Acid Catalyzed Carbonyl–Olefin Metathesis

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30

Gordon, Christopher P., and Christophe Copéret. "Probing the Electronic Structure of Spectator Oxo Ligands by 17O NMR Spectroscopy." CHIMIA International Journal for Chemistry 74, no. 4 (April 29, 2020): 225–31. http://dx.doi.org/10.2533/chimia.2020.225.

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Spectator oxo ligands are ubiquitous in catalysis, in particular in olefin epoxidation and olefin metathesis. Here we use computationally derived 17O NMR parameters to probe the electronic structure of spectator oxo ligands in these two reactions. We show that 17O NMR parameters allow to distinguish between doubly-bonded and triply-bonded oxo ligands, giving detailed insights into the frontier molecular orbitals involved in the metaloxo bonds along the reaction pathway. On the one hand, our study shows that in olefin epoxidation catalysed by methyltrioxorhenium (MTO), the oxo ligand significantly changes its bonding mode upon formation of the oxygen-transferring Re-oxo-bisperoxo-species, changing its nature from a doubly bonded to a triply bonded oxo ligand. On the other hand, only minor changes in the binding mode are found along the olefin metathesis reaction pathway with Mo- and W-based oxo-alkylidene species, in which the oxo ligand behaves as a triply bonded ligand throughout the reaction. This finding contrasts earlier studies that proposed that the change of binding mode of the oxo ligand was key to metallacyclobutane formation.

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31

Liggio, J., and S. M. Li. "Reversible and irreversible processing of biogenic olefins on acidic aerosols." Atmospheric Chemistry and Physics Discussions 7, no. 4 (August 14, 2007): 11973–2009. http://dx.doi.org/10.5194/acpd-7-11973-2007.

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Abstract. Recent evidence has suggested that heterogeneous chemistry of oxygenated hydrocarbons, primarily carbonyls, plays a role in the formation of secondary organic aerosol (SOA); however, evidence is emerging that direct uptake of alkenes on acidic aerosols does occur and can contribute to SOA formation. In the present study, significant uptake of monoterpenes, oxygenated monoterpenes and sesquiterpenes to acidic sulfate aerosols is found under various conditions in a reaction chamber. Proton transfer mass spectrometry is used to quantify the organic gases, while an aerosol mass spectrometer is used to quantify the organic mass uptake and obtain structural information for heterogeneous products. Aerosol mass spectra are consistent with several mechanisms including acid catalyzed olefin hydration, cationic polymerization and organic ester formation, while measurable decreases in the sulfate mass on a per particle basis suggest that the formation of organosulfate compounds is also likely. A portion of the heterogeneous reactions appears to be reversible, consistent with reversible olefin hydration reactions. A slow increase in the organic mass after a fast initial uptake is attributed to irreversible reactions, consistent with polymerization and organosulfate formation. Uptake coefficients (γ) were estimated for a fast initial uptake governed by the mass accommodation coefficient (α) and ranged from 1×10-6–2.5×10−2. Uptake coefficients for a subsequent slower reactive uptake ranged from 1×10-7–1×10-4. These processes are estimated to potentially produce greater than 2.5 μg m−3 of SOA from the various biogenic hydrocarbons under atmospheric conditions, which can be highly significant given the large array of atmospheric olefins.

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32

Liggio, J., and S. M. Li. "Reversible and irreversible processing of biogenic olefins on acidic aerosols." Atmospheric Chemistry and Physics 8, no. 7 (April 9, 2008): 2039–55. http://dx.doi.org/10.5194/acp-8-2039-2008.

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Abstract. Recent evidence has suggested that heterogeneous chemistry of oxygenated hydrocarbons, primarily carbonyls, plays a role in the formation of secondary organic aerosol (SOA); however, evidence is emerging that direct uptake of alkenes on acidic aerosols does occur and can contribute to SOA formation. In the present study, significant uptake of monoterpenes, oxygenated monoterpenes and sesquiterpenes to acidic sulfate aerosols is found under various conditions in a reaction chamber. Proton transfer mass spectrometry is used to quantify the organic gases, while an aerosol mass spectrometer is used to quantify the organic mass uptake and obtain structural information for heterogeneous products. Aerosol mass spectra are consistent with several mechanisms including acid catalyzed olefin hydration, cationic polymerization and organic ether formation, while measurable decreases in the sulfate mass on a per particle basis suggest that the formation of organosulfate compounds is also likely. A portion of the heterogeneous reactions appears to be reversible, consistent with reversible olefin hydration reactions. A slow increase in the organic mass after a fast initial uptake is attributed to irreversible reactions, consistent with polymerization and organosulfate formation. Uptake coefficients (γ) were estimated for a fast initial uptake governed by the mass accommodation coefficient (α) and ranged from 1×10-6-2.5×10-2. Uptake coefficients for a subsequent slower reactive uptake ranged from 1×10-7-1×10-4. These processes may potentially lead to a considerable amount of SOA from the various biogenic hydrocarbons under acidic conditions, which can be highly significant for freshly nucleated aerosols, particularly given the large array of atmospheric olefins.

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33

Astruc, Didier, Abdou K. Diallo, Sylvain Gatard, Liyuan Liang, Cátia Ornelas, Victor Martinez, Denise Méry, and Jaime Ruiz. "Olefin metathesis in nano-sized systems." Beilstein Journal of Organic Chemistry 7 (January 19, 2011): 94–103. http://dx.doi.org/10.3762/bjoc.7.13.

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The interplay between olefin metathesis and dendrimers and other nano systems is addressed in this mini review mostly based on the authors’ own contributions over the last decade. Two subjects are presented and discussed: (i) The catalysis of olefin metathesis by dendritic nano-catalysts via either covalent attachment (ROMP) or, more usefully, dendrimer encapsulation – ring closing metathesis (RCM), cross metathesis (CM), enyne metathesis reactions (EYM) – for reactions in water without a co-solvent and (ii) construction and functionalization of dendrimers by CM reactions.

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34

Leigh, William J., Debbie T. Frendo, and Paul J. Klawunn. "Organic reactions in liquid crystalline solvents. 1. The thermal cis–trans isomerization of a bulky olefin in cholesteric liquid crystalline solvents." Canadian Journal of Chemistry 63, no. 8 (August 1, 1985): 2131–38. http://dx.doi.org/10.1139/v85-351.

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The effect of cholesteric liquid crystalline solvents on the energetics of rotational thermal cis–trans isomerization of olefins has been examined. Rate constants have been obtained over a 70-degree temperature range for isomerization of trans-1,2-di-(4-cyanophenyl)-1,2-diphenylethylene in two isotropic solvents and three cholesteric liquid crystals and the Arrhenius parameters determined. The rates of isomerization are found to be consistently slower in the liquid crystalline phases compared to the isotropic solvents. The Arrhenius parameters for isomerization of the olefin in the isotropic solvents (Ea = 34.8 ± 0.3 kcal/mol; ΔS≠ = −1.5 ± 0.5 e.u.) compare favourably with reported values for its isomerization in benzene solution. In the cholesteric phases, Ea is consistently 1–1.5 kcal/mol higher and ΔS≠ slightly more positive than the corresponding values for the isotropic solvents. The results are tentatively rationalized in terms of disruption of liquid crystalline order as the olefin twists from its pseudo-planar, ground state geometry through the globular, twisted transition state. The magnitude of this effect is proposed to depend on both the difference in steric bulk of the ground and transition states and the "tightness" of the solvation shell seen by the isomerizing molecule. It is believed that in the present case the observed effects are somewhat truncated as a result of rather poor solvation of the bulky olefin in the liquid crystalline phases.

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35

Reymond, Sébastien, Laurent Ferrié, Amandine Guérinot, Patrice Capdevielle, and Janine Cossy. "Chemoselective reactions: Toward the synthesis of biologically active natural products with anticancer activities." Pure and Applied Chemistry 80, no. 8 (January 1, 2008): 1683–91. http://dx.doi.org/10.1351/pac200880081683.

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Leucascandrolide A and migrastatin were synthesized efficiently by using chemoselective reactions such as olefin metatheses. The use of an iron-catalyzed cross-coupling reaction overcame difficulties encountered with palladium-catalyzed processes in our synthetic approach toward spirangien A.

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36

Grau, Benedikt W., and Svetlana B. Tsogoeva. "Iron-Catalyzed Carbonyl–Alkyne and Carbonyl–Olefin Metathesis Reactions." Catalysts 10, no. 9 (September 21, 2020): 1092. http://dx.doi.org/10.3390/catal10091092.

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Construction of carbon–carbon bonds is one of the most important tools for the synthesis of complex organic molecules. Among multiple possibilities are the carbonyl–alkyne and carbonyl–olefin metathesis reactions, which are used to form new carbon–carbon bonds between carbonyl derivatives and unsaturated organic compounds. As many different approaches have already been established and offer reliable access to C=C bond formation via carbonyl–alkyne and carbonyl–olefin metathesis, focus is now shifting towards cost efficiency, sustainability and environmentally friendly metal catalysts. Iron, which is earth-abundant and considered as an eco-friendly and inexpensive option in comparison to traditional metal catalysts, fulfils these requirements. Hence, the focus of this review is on recent advances in the iron-catalyzed carbonyl–alkyne, carbonyl–olefin and related C–O/C–O metathesis reactions. The still large research potential for ecologically and economically attractive and sustainable iron-based catalysts is demonstrated.

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37

Astruc, D. "The Olefin Metathesis Reactions in Dendrimers." Oil & Gas Science and Technology - Revue de l'IFP 62, no. 6 (October 30, 2007): 787–97. http://dx.doi.org/10.2516/ogst:2007055.

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38

Zieliński, Grzegorz K., and Karol Grela. "Tandem Catalysis Utilizing Olefin Metathesis Reactions." Chemistry - A European Journal 22, no. 28 (June 14, 2016): 9417. http://dx.doi.org/10.1002/chem.201602627.

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39

Zieliński, Grzegorz K., and Karol Grela. "Tandem Catalysis Utilizing Olefin Metathesis Reactions." Chemistry - A European Journal 22, no. 28 (May 20, 2016): 9440–54. http://dx.doi.org/10.1002/chem.201505136.

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40

Bhat, Bilal A., and Bashir A. Shairgojray. "Applications of Micelles in Catalyzing Organic Reactions." Mini-Reviews in Organic Chemistry 17, no. 3 (April 28, 2020): 289–96. http://dx.doi.org/10.2174/1570193x16666181228112834.

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: Micellar chemistry is gaining considerable interest among organic chemists because these reactions are carried out in environmentally benign solvents like water. Owing to the exhaustive use of toxic solvents in carrying out the different chemical reactions, there is a pressing need for alternative approaches either environmental friendly or having minimum impact on the environment. In this article, we aim to discuss the various aspects of micellar chemistry viz-a-viz its role in guiding the chemical reactions. Micelles help to drive various kinds of organic reactions including oxidations, reductions, carbon-carbon bond formation, carbon-heteroatom bond formation, multi-component reactions, Pd-coupling reaction, olefin metathesis reaction, Morita-Baylis-Hillman reaction, etc. in water.

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41

Kakiuchi, Fumitoshi, Naoki Kimura, Shiori Katta, Yoichi Kitazawa, and Takuya Kochi. "Deuterium-Labeling Studies on the C–H/Olefin Coupling of Aromatic Ketones Catalyzed by Fe(PMe3)4." Synthesis 53, no. 18 (May 19, 2021): 3383–89. http://dx.doi.org/10.1055/s-0040-1706040.

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AbstractDeuterium-labeling experiments were performed for the Fe(PMe3)4-catalyzed C–H/olefin coupling using a deuterium-labeled aromatic ketone with various alkenes. While the reactions with a variety of alkenes provided the linear alkylation products formed via 1,2-insertion of alkene into an Fe–H bond, the reversible 2,1-insertion proceeded during the reaction highly depends on the choice of the alkene. No H/D scrambling resulting from 2,1-insertion/β-elimination was detected for the reactions with a vinylsilane and N-vinylcarbazole, but the reactions with styrenes are considered to involve rapid 2,1-insertion/ β-elimination processes to cause significant levels of H/D scrambling.

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42

Sales, Rita N., Samantha K. Callear, Pedro D. Vaz, and Carla D. Nunes. "Substrate–Solvent Crosstalk—Effects on Reaction Kinetics and Product Selectivity in Olefin Oxidation Catalysis." Chemistry 3, no. 3 (July 19, 2021): 753–64. http://dx.doi.org/10.3390/chemistry3030054.

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In this work, we explored how solvents can affect olefin oxidation reactions catalyzed by MCM-bpy-Mo catalysts and whether their control can be made with those players. The results of this study demonstrated that polar and apolar aprotic solvents modulated the reactions in different ways. Experimental data showed that acetonitrile (aprotic polar) could largely hinder the reaction rate, whereas toluene (aprotic apolar) did not. In both cases, product selectivity at isoconversion was not affected. Further insights were obtained by means of neutron diffraction experiments, which confirmed the kinetic data and allowed for the proposal of a model based on substrate–solvent crosstalk by means of hydrogen bonding. In addition, the model was also validated in the ring-opening reaction (overoxidation) of styrene oxide to benzaldehyde, which progressed when toluene was the solvent (reaching 31% styrene oxide conversion) but was strongly hindered when acetonitrile was used instead (reaching only 7% conversion) due to the establishment of H-bonds in the latter. Although this model was confirmed and validated for olefin oxidation reactions, it can be envisaged that it may also be applied to other catalytic reaction systems where reaction control is critical, thereby widening its use.

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43

Tanizume, Shusei, Toshihiro Yoshimura, Katsunori Ishii, and Mikihiro Nomura. "Control of Sequential MTO Reactions through an MFI-Type Zeolite Membrane Contactor." Membranes 10, no. 2 (February 7, 2020): 26. http://dx.doi.org/10.3390/membranes10020026.

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A membrane for controlling methanol-to-olefin (MTO) reactions was developed, which featured an MFI-type zeolite membrane (Si/Al = 25) that was synthesized on a porous α-alumina substrate using a secondary growth method. Here, the H2/SF6 permeance ratios were between 150 and 450. The methanol conversion rate was 70% with 38% ethylene selectivity and 28% propylene selectivity as determined using a cross-flow membrane contactor. In order to improve the olefin selectivity of the membrane, the MFI zeolite layer (Si/Al = ∞) was coated on an MFI-type zeolite membrane (Si/Al = 25). Using this two-layered membrane system, the olefin selectivity value increased to 85%; this was 19% higher than the value obtained during the single-layer membrane system.

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44

Xia, Wei, Qi Sun, Shang Wen Liu, Lin Ping Qiang, and Yuan Cun Cui. "SAPO-34/SiO₂ Catalysts for the Transformation of Ethanol into Propylene." Advanced Materials Research 1004-1005 (August 2014): 707–10. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.707.

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Ethanol has great potential to be a candidate for the source of light olefins such as ethylene and propylene. However, ethanol to olefin (ETO) process has not been fully investigated. In this work, the conversion reactions of ethanol were carried out at 673 K under atmospheric pressure on SAPO-34 and SAPO-34/SiO2 catalysts. SAPO-34 and SAPO-34/SiO2 exhibit higher selectivity for propylene than H-ZSM-5 zeolite catalysts do. The SAPO-34 with silica binder showed better catalytic performance for the transformation of ethanol to propylene than the SAPO-34 catalyst.

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45

Nicks, François, Yannick Borguet, Sébastien Delfosse, Dario Bicchielli, Lionel Delaude, Xavier Sauvage, and Albert Demonceau. "Microwave-Assisted Ruthenium-Catalyzed Reactions." Australian Journal of Chemistry 62, no. 3 (2009): 184. http://dx.doi.org/10.1071/ch08510.

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Since the first reports on the use of microwave irradiation to accelerate organic chemical transformations, a plethora of papers has been published in this field. In most examples, microwave heating has been shown to dramatically reduce reaction times, increase product yields, and enhance product purity by reducing unwanted side reactions compared with conventional heating methods. The present contribution aims at illustrating the advantages of this technology in homogeneous catalysis by ruthenium complexes and, when data are available, at comparing microwave-heated and conventionally heated experiments. Selected examples refer to olefin metathesis, isomerization reactions, 1,3-dipolar cycloadditions, atom transfer radical reactions, transfer hydrogenation reactions, and H/D exchange reactions.

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46

Sabatino, Valerio, and Thomas R. Ward. "Aqueous olefin metathesis: recent developments and applications." Beilstein Journal of Organic Chemistry 15 (February 14, 2019): 445–68. http://dx.doi.org/10.3762/bjoc.15.39.

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Olefin metathesis is one of the most powerful C–C double-bond-forming reactions. Metathesis reactions have had a tremendous impact in organic synthesis, enabling a variety of applications in polymer chemistry, drug discovery and chemical biology. Although challenging, the possibility to perform aqueous metatheses has become an attractive alternative, not only because water is a more sustainable medium, but also to exploit biocompatible conditions. This review focuses on the progress made in aqueous olefin metatheses and their applications in chemical biology.

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47

Nifant’ev, Ilya E., Ildar I. Salakhov, and Pavel V. Ivchenko. "Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry." Molecules 27, no. 21 (October 23, 2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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48

Nifant’ev, Ilya E., Ildar I. Salakhov, and Pavel V. Ivchenko. "Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry." Molecules 27, no. 21 (October 23, 2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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49

Nifant’ev, Ilya E., Ildar I. Salakhov, and Pavel V. Ivchenko. "Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry." Molecules 27, no. 21 (October 23, 2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Abstract:

Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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50

Nifant’ev, Ilya E., Ildar I. Salakhov, and Pavel V. Ivchenko. "Transition Metal–(μ-Cl)–Aluminum Bonding in α-Olefin and Diene Chemistry." Molecules 27, no. 21 (October 23, 2022): 7164. http://dx.doi.org/10.3390/molecules27217164.

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Abstract:

Olefin and diene transformations, catalyzed by organoaluminum-activated metal complexes, are widely used in synthetic organic chemistry and form the basis of major petrochemical processes. However, the role of M–(μ-Cl)–Al bonding, being proven for certain >C=C< functionalization reactions, remains unclear and debated for essentially more important industrial processes such as oligomerization and polymerization of α-olefins and conjugated dienes. Numerous publications indirectly point at the significance of M–(μ-Cl)–Al bonding in Ziegler–Natta and related transformations, but only a few studies contain experimental or at least theoretical evidence of the involvement of M–(μ-Cl)–Al species into catalytic cycles. In the present review, we have compiled data on the formation of M–(μ-Cl)–Al complexes (M = Ti, Zr, V, Cr, Ni), their molecular structure, and reactivity towards olefins and dienes. The possible role of similar complexes in the functionalization, oligomerization and polymerization of α-olefins and dienes is discussed in the present review through the prism of the further development of Ziegler–Natta processes and beyond.

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Journal articles on the topic 'Olefin reactions'

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