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Journal articles on the topic 'Allyl transfer reactions'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 February 2022

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1

Easton, Christopher J., and Ilse M. Scharfbillig. "Homolytic allyl transfer reactions of 1- and 3-alkyl-substituted allyltributylstannanes." Journal of Organic Chemistry 55, no. 1 (January 1990): 384–86. http://dx.doi.org/10.1021/jo00288a076.

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2

Lee, Ikchoon, Chang Kon Kim, and Bon-Su Lee. "Theoretical studies of the identity allyl transfer reactions." Journal of Physical Organic Chemistry 8, no. 7 (July 1995): 473–83. http://dx.doi.org/10.1002/poc.610080706.

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3

Lee, Ikchoon, Chang Kon Kim, and Bon-Su Lee. "Ab initio molecular orbital studies of nonidentity allyl transfer reactions." Journal of Computational Chemistry 16, no. 8 (August 1995): 1045–54. http://dx.doi.org/10.1002/jcc.540160811.

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4

Arisawa, Mieko, and Masahiko Yamaguchi. "Transition-metal-catalyzed synthesis of organosulfur compounds." Pure and Applied Chemistry 80, no. 5 (January 1, 2008): 993–1003. http://dx.doi.org/10.1351/pac200880050993.

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Rhodium complexes are efficient catalysts for the synthesis of organosulfur compounds. They catalyze the addition reaction of organosulfur groups to unsaturated compounds, the substitution of C-H with organosulfur groups, and single-bond metathesis reactions. They cleave S-S bonds and transfer the organosulfur groups to various organic and inorganic molecules, including alkynes, allenes, disulfides, sulfur, isonitriles, imines, diphosphines, thiophosphinites, hydrogen, 1-alkylthio-1-alkynes, thioesters, and allyl sulfides.

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5

Pitteloud, Jean-Philippe, Yong Liang, and Stanislaw F. Wnuk. "Chemoselective Transfer of Allyl or Phenyl Group from Allyl(phenyl)germanes in Pd-catalyzed Reactions with Aryl Halides." Chemistry Letters 40, no. 9 (September 5, 2011): 967–69. http://dx.doi.org/10.1246/cl.2011.967.

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6

Morais, Latino Loureiro, Hideya Yuasa, Khalil Bennis, Isabelle Ripoche, and France-Isabelle Auzanneau. "Chemoenzymatic synthesis of thio-nod factor intermediates Enzymatic transfer of glucosamine on thiochitobiose derivatives." Canadian Journal of Chemistry 84, no. 4 (April 1, 2006): 587–96. http://dx.doi.org/10.1139/v06-043.

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The chemoenzymatic syntheses of thioanalogues of nodulation factors in which the nonreducing end glucosamine residue is available for the introduction of the fatty acid moiety at the free NH2 group are reported. We are describing the chemical synthesis of UDP-GlcNH2 and its use in the enzymatic transfer of GlcNH2 by the bovine galactosyltransferase (EC 2.4.1.90) onto O-4 of the nonreducing end N-acetylglucosamine residues of chitobiose, thiochitobiose, and allyl thiochitobioside. The enzymatic reactions on chitobiose and thiochitobiose were followed by TLC and MALDI MS and showed about 50% conversion of the disaccharides to the desired products. However, these reducing trisaccharides could not be obtained totally free of salts and degraded on ion exchange chromatography. Thus, we investigated the enzymatic transfer on the nonreducing allyl thiochitobioside analogue. We describe here the chemical synthesis of this thiodisaccharide and the enzymatic transfer of GlcNH2 at O-4 of its nonreducing end glucosamine residue to give the desired allyl thiotrisaccharide. This thiotrisaccharide was obtained pure in 41% yield and was characterized by 1H NMR (HSQC) and HRMS.Key words: nodulation factors, synthesis, enzymatic transfer, thiooligosaccharides, UDP-glucosamine.

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7

Yoshimi, Yasuharu, Hirotomo Kanai, Keisuke Nishikawa, Yasushi Ohta, Yoshiki Okita, Kousuke Maeda, and Toshio Morita. "Electron transfer promoted photochemical reductive radical cyclization reactions of allyl 2-bromoaryl ethers." Tetrahedron Letters 54, no. 19 (May 2013): 2419–22. http://dx.doi.org/10.1016/j.tetlet.2013.02.103.

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8

Zaccaria, Francesco, Peter H. M. Budzelaar, Cristiano Zuccaccia, Roberta Cipullo, Alceo Macchioni, Vincenzo Busico, and Christian Ehm. "Chain Transfer to Solvent and Monomer in Early Transition Metal Catalyzed Olefin Polymerization: Mechanisms and Implications for Catalysis." Catalysts 11, no. 2 (February 5, 2021): 215. http://dx.doi.org/10.3390/catal11020215.

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Even after several decades of intense research, mechanistic studies of olefin polymerization by early transition metal catalysts continue to reveal unexpected elementary reaction steps. In this mini-review, the recent discovery of two unprecedented chain termination processes is summarized: chain transfer to solvent (CTS) and chain transfer to monomer (CTM), leading to benzyl/tolyl and allyl type chain ends, respectively. Although similar transfer reactions are well-known in radical polymerization, only very recently they have been observed also in olefin insertion polymerization catalysis. In the latter context, these processes were first identified in Ti-catalyzed propene and ethene polymerization; more recently, CTS was also reported in Sc-catalyzed styrene polymerization. In the Ti case, these processes represent a unique combination of insertion polymerization, organic radical chemistry and reactivity of a M(IV)/M(III) redox couple. In the Sc case, CTS occurs via a σ-bond metathesis reactivity, and it is associated with a significant boost of catalytic activity and/or with tuning of polystyrene molecular weight and tacticity. The mechanistic studies that led to the understanding of these chain transfer reactions are summarized, highlighting their relevance in olefin polymerization catalysis and beyond.

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9

Schwan, Adrian L., and John Warkentin. "The reactions of simple dimethylallylamines with dimethyl acetylenedicarboxylate. Formation of 1-dimethylamino-2-allylmaleates via formal allyl transfer." Canadian Journal of Chemistry 66, no. 7 (July 1, 1988): 1686–94. http://dx.doi.org/10.1139/v88-273.

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Tertiary amines bearing two methyl groups and an allylic substituent (X) react with dimethyl acetylenedicarboxylate (DMAD) to afford the corresponding 1-dimethylamino-2-X′ maleates, in which X′ is the allylic isomer of X. The mechanism postulated involves reversible formation of a zwitterion by attack of the amine at an sp-carbon of DMAD. The zwitterion then undergoes intramolecular allyl transfer, through a 6-membered transition state. Evidence for a zwitterionic intermediate (quaternary ammonium allenolate) includes capture of the allenolate centre by intramolecular addition to a carbonyl group and by proton transfer from chloroform.

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10

Pitteloud, Jean-Philippe, Yong Liang, and Stanislaw F. Wnuk. "ChemInform Abstract: Chemoselective Transfer of Allyl or Phenyl Group from Allyl(phenyl)germanes in Pd-Catalyzed Reactions with Aryl Halides." ChemInform 43, no. 8 (January 27, 2012): no. http://dx.doi.org/10.1002/chin.201208048.

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11

Franco, Delphine, Sandra Olivero, and Elisabet Duñach. "Intramolecular allyl transfer reactions catalyzed by electrogenerated nickel-bipyridine complexes: electrosynthesis of homoallylic alcohols." Electrochimica Acta 42, no. 13-14 (January 1997): 2159–64. http://dx.doi.org/10.1016/s0013-4686(97)85493-x.

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12

Potapov, Vladimir A., Roman S. Ishigeev, Lyudmila A. Belovezhets, Irina V. Shkurchenko, and Svetlana V. Amosova. "New Water-Soluble Condensed Heterocyclic Compounds with Antimicrobial Activity Based on Annulation Reactions of 8-Quinolinesulfenyl Halides with Natural Products and Alkenes." Applied Sciences 11, no. 18 (September 14, 2021): 8532. http://dx.doi.org/10.3390/app11188532.

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The annulation reactions of 8-quinolinesulfenyl halides with natural products and alkenes affording new water-soluble [1,4]thiazino[2,3,4-ij]quinolin-4-ium derivatives in high or quantitative yields are developed in this study. The reactions with styrene derivatives and terminal alkenes including allyl arenes proceed in a regioselective manner but with the opposite regiochemistry. The reactions with terminal alkenes including allyl arenes occur in an anti-Markovnikov fashion (regarding addition of the 8-quinolinesulfenyl electrophile to the double bond) to give 2-organyl-2H,3H-[1,4]thiazino[2,3,4-ij]quinolin-4-ium halides, while the reactions with styrene derivatives proceed in a Markovnikov fashion, leading to 3-substituted condensed heterocyclic compounds. In general, styrene derivatives demonstrate higher reactivity in the annulation reactions compared to the terminal alkenes. Antimicrobial activity of novel water-soluble compounds against Enterococcus durans, Bacillus subtilis and Escherichia coli are evaluated. The compounds with high antimicrobial activity are found. The annulation products of the reactions of 8-quinolinesulfenyl halides with 1H-indene, eugenol, methyl eugenol and 1-heptene, are superior in their activity compared to the antibiotic gentamicin.

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13

Bowen, Richard D. "Hydrogen transfer reactions in the decomposition of isolated ‘onium’ ions containing an incipient allyl cation." J. Chem. Soc., Chem. Commun., no. 12 (1985): 807–9. http://dx.doi.org/10.1039/c39850000807.

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14

Cristol, Stanley J., Dieter Braun, George C. Schloemer, and Bart J. Vanden Plas. "Photochemical transformations. 42. Photoreactions of certain bridged bicyclic and tricyclic chlorides and bromides containing aromatic chromophores." Canadian Journal of Chemistry 64, no. 6 (June 1, 1986): 1081–84. http://dx.doi.org/10.1139/v86-181.

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Irradiations of a number of bicyclic and tricyclic bromides and chlorides containing aromatic rings have been carried out. With the allylic chlorides 2-Cl and 3-Cl, triplet-sensitized photoreactions in acetone (or in acetonitrile with acetophenone sensitizer) lead to allylic scrambling and allyl-to-cyclopropyl isomerization to 5-Cl, while the corresponding bromides, under similar conditions, give allylic scrambling, photo-Wagner–Meerwein rearrangement, and photosolvolysis, but no allyl-to-cyclopropyl isomerization. The differences in reaction types are ascribed to the requirement for intramolecular electron transfer for the "ionic" reactions, which may be exothermic in the triplet states of the bromides, but not in those of the chlorides. In direct irradiations in acetic acid with 254-nm light, the singlet state of the chloride 2-Cl is photoactive in the "ionic" sense, giving a mixture of acetates, benzofluorenes, and 1-methylfluoranthene. The latter hydrocarbon is the major product in the direct irradiation of 5-Cl in acetic acid, along with a mixture of acetates. The photochemical results are contrasted with ground-state solvolyses of these compounds.

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15

FRANCO, D., S. OLIVERO, and E. DUNACH. "ChemInform Abstract: Intramolecular Allyl Transfer Reactions Catalyzed by Electrogenerated Nickel-Bipyridine Complexes: Electrosynthesis of Homoallylic Alcohols." ChemInform 28, no. 37 (August 3, 2010): no. http://dx.doi.org/10.1002/chin.199737044.

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16

JONCZYK, A., and T. RADWAN-PYTLEWSKI. "ChemInform Abstract: Phase-Transfer Catalysis (PTC): A Convenient Tool for Generation and Reactions of Allyl Sulfonyl Carbanions." ChemInform 27, no. 27 (August 5, 2010): no. http://dx.doi.org/10.1002/chin.199627071.

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17

Haufe, Günter, Oliver G. J. Meyer, and Christian Mück-Lichtenfeld. "Addition of Dihalocarbenes to Vinyl Fluorides. Chemical Consequences of Fluorine Substitution. Part 3." Collection of Czechoslovak Chemical Communications 67, no. 10 (2002): 1493–504. http://dx.doi.org/10.1135/cccc20021493.

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1-Fluoro-1-phenylethene (1a) or 1-(4-chlorophenyl)-1-fluoroethene (1b) and 2-fluorooct-1-ene (4), on reaction with chloroform and sodium hydroxide, in a two-phase system in the presence of a phase transfer catalyst, gave the corresponding dichlorocyclopropanes in good yields. In a competition experiment, 1a was shown to be slightly more reactive than styrene itself. AM1 calculations predict reasonable activation barriers for these reactions although the relative reactivity observed in the experiment is not reproduced. For the (E)- and (Z)-1-fluoro-2-phenylethenes (3), higher activation barriers were calculated, in agreement with the observation that these alkenes did not react with dichlorocarbene under these conditions. The dibromocarbene addition to 1a gave 1,1-dibromo-2-fluoro-2-phenylcyclopropane (8), which on heating with silver salts in acetic acid yielded 3-acetoxy- 2-bromo-1-fluoro-1-phenylprop-1-ene (9) by a cyclopropyl-allyl rearrangement.

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18

Zhang, Xinyu, Bo Lin, Jianhui Chen, Jiajia Chen, Yanshu Luo, and Yuanzhi Xia. "Synthesis of Sulfimides and N-Allyl-N-(thio)amides by Ru(II)-Catalyzed Nitrene Transfer Reactions of N-Acyloxyamides." Organic Letters 23, no. 3 (January 11, 2021): 819–25. http://dx.doi.org/10.1021/acs.orglett.0c04043.

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19

Sánchez-Barba, Luis F., David L. Hughes, Simon M. Humphrey, and Manfred Bochmann. "Ligand Transfer Reactions of Mixed-Metal Lanthanide/Magnesium Allyl Complexes with β-Diketimines: Synthesis, Structures, and Ring-Opening Polymerization Catalysis." Organometallics 25, no. 4 (February 2006): 1012–20. http://dx.doi.org/10.1021/om050892h.

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20

Trost, Barry M., Zhongxing Huang, and Ganesh M. Murhade. "Catalytic palladium-oxyallyl cycloaddition." Science 362, no. 6414 (November 1, 2018): 564–68. http://dx.doi.org/10.1126/science.aau4821.

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Exploration of intermediates that enable chemoselective cycloaddition reactions and expeditious construction of fused- or bridged-ring systems is a continuous challenge for organic synthesis. As an intermediate of interest, the oxyallyl cation has been harnessed to synthesize architectures containing seven-membered rings via (4+3) cycloaddition. However, its potential to access five-membered skeletons is underdeveloped, largely due to the thermally forbidden (3+2) pathway. Here, the combination of a tailored precursor and a Pd(0) catalyst generates a Pd-oxyallyl intermediate that cyclizes with conjugated dienes to produce a diverse array of tetrahydrofuran skeletons. The cycloaddition overrides conventional (4+3) selectivity by proceeding through a stepwise pathway involving a Pd-allyl transfer and ring closure sequence. Subsequent treatment of the (3+2) adducts with a palladium catalyst converts the heterocycles to the carbocyclic cyclopentanones.

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21

Lu, Yanju, Zhendong Zhao, Yuxiang Chen, Jing Wang, Shichao Xu, and Yan Gu. "Synthesis of allyl acrylpimarate by microwave irradiation and phase-transfer catalytic reaction and its UV-curing reactions as a new monomer." Progress in Organic Coatings 109 (August 2017): 9–21. http://dx.doi.org/10.1016/j.porgcoat.2017.04.006.

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22

Molina-Gutiérrez, Samantha, Sara Dalle Vacche, Alessandra Vitale, Vincent Ladmiral, Sylvain Caillol, Roberta Bongiovanni, and Patrick Lacroix-Desmazes. "Photoinduced Polymerization of Eugenol-Derived Methacrylates." Molecules 25, no. 15 (July 29, 2020): 3444. http://dx.doi.org/10.3390/molecules25153444.

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Biobased monomers have been used to replace their petroleum counterparts in the synthesis of polymers that are aimed at different applications. However, environmentally friendly polymerization processes are also essential to guarantee greener materials. Thus, photoinduced polymerization, which is low-energy consuming and solvent-free, rises as a suitable option. In this work, eugenol-, isoeugenol-, and dihydroeugenol-derived methacrylates are employed in radical photopolymerization to produce biobased polymers. The polymerization is monitored in the absence and presence of a photoinitiator and under air or protected from air, using Real-Time Fourier Transform Infrared Spectroscopy. The polymerization rate of the methacrylate double bonds was affected by the presence and reactivity of the allyl and propenyl groups in the eugenol- and isoeugenol-derived methacrylates, respectively. These groups are involved in radical addition, degradative chain transfer, and termination reactions, yielding crosslinked polymers. The materials, in the form of films, are characterized by differential scanning calorimetry, thermogravimetric, and contact angle analyses.

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23

Pei, Linsen, and James M. Farrar. "Velocity Map Imaging Study of Ion–Radical Chemistry: Charge Transfer and Carbon–Carbon Bond Formation in the Reactions of Allyl Radicals with C+." Journal of Physical Chemistry A 120, no. 31 (July 27, 2016): 6122–28. http://dx.doi.org/10.1021/acs.jpca.6b05699.

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24

Klein, Hans-Friedrich, Michael Helwig, Udo Koch, Goetz Lull, Marko Tadic, Carl Krüger, and Peter Hofmann. "Diolefinbis(trimethyIphosphine)cobalt(0) Compounds: Stable Organometallic Radicals with Distorted Ground State Structures." Zeitschrift für Naturforschung B 43, no. 11 (November 1, 1988): 1427–38. http://dx.doi.org/10.1515/znb-1988-1107.

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Abstract Diolefincobalt(O) complexes Co(L2)(PMe3)2 {L2 -[CH2 = CHSi(OMe)2]2O (1), [CH2 =CHSi(OEt)2]2O (2), (CH2 =CHCH2)2SiMe2 (3), [(CH2 =CHCH2)2N]2CH2 (4)} have been synthesized from Co(C5H8)(PMe3)3 and diolefins at ambient temperatures. Reactions with allyl ethers or with allyltin or allylphosphorus compounds involve transfer of allyl groups to the cobalt, while allylamine simply replaces cyclopentene (C5H8) to give Co(CH2 =CHCH2NH2)(PMe3)3 (5). Cationic cobalt(I) complexes containing olefin ligands as in 1-4 could not be obtained under conditions where norbornadiene readily gave [Co(C7H8)(PMe3)3 ]BF4 (6). Paramagnetic 4 shows a magnetic moment μeff = 2.0 μв (between 3.6 and 293 K), corresponding to one unpaired electron per cobalt atom. Compound 4 crystallizes in the space group P21/c with Z = 4, a = 14.986(4), b = 17.223(5), c = 15.436(3) Å,β = 117.98(2)°, V = 3518.4 Å3 . Each cobalt atom is η4-coordinated to a diolefin involving the smaller of two possible chelating rings. The Co-C distances range only from 2.029(6) to 2.058(6) Å for the olefin ligands, whereas Co-P bond lengths at each cobalt differ significantly: Co1-P1 2.188(2), Co1-P2 2.248(2); Co2-P3 2.185(2), Co2-P4 2.258(2) Å. This feature of two significantly different Co-L bond lengths is hitherto seen in all structurally characterized (bisolefin)CoL2 complexes (L = PMe3, CH3CN) and can be rationalized by molecular orbital calculations (Extended Hückel) on the 17 electron model system (PH3)2Co(C2H4)2.

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25

Motoyama, Yukihiro, Shiori Hanada, Kazuya Shimamoto, and Hideo Nagashima. "A coordinatively unsaturated ruthenium methoxide as a highly effective catalyst for the halogen atom-transfer radical cyclization of N-allyl dichloroacetamides and related reactions." Tetrahedron 62, no. 12 (March 2006): 2779–88. http://dx.doi.org/10.1016/j.tet.2006.01.011.

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26

Yadav, Ganapati D., and Priyal M. Bisht. "Intensification and Selectivities in Complex Multiphase Reactions: Insight into the Selectivity of Liquid−Liquid Phase-Transfer-Catalyzed O-Alkylation ofp-Methoxyphenol with Allyl Bromide." Industrial & Engineering Chemistry Research 44, no. 5 (March 2005): 1273–83. http://dx.doi.org/10.1021/ie049710u.

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27

Sai, Masahiro, Hideki Yorimitsu, and Koichiro Oshima. "Allyl-, Allenyl-, and Propargyl-Transfer Reactions through Cleavage of CC Bonds Catalyzed by an N-Heterocyclic Carbene/Copper Complex: Synthesis of Multisubstituted Pyrroles." Angewandte Chemie 123, no. 14 (March 4, 2011): 3352–56. http://dx.doi.org/10.1002/ange.201100631.

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28

Sai, Masahiro, Hideki Yorimitsu, and Koichiro Oshima. "Allyl-, Allenyl-, and Propargyl-Transfer Reactions through Cleavage of CC Bonds Catalyzed by an N-Heterocyclic Carbene/Copper Complex: Synthesis of Multisubstituted Pyrroles." Angewandte Chemie International Edition 50, no. 14 (March 4, 2011): 3294–98. http://dx.doi.org/10.1002/anie.201100631.

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29

Shakhmaev, Rinat N., Alisa Sh Sunagatullina, and Vladimir V. Zorin. "SYNTHESIS OF INDIVIDUAL ISOMERS OF 2-(3-CHLOROPROP-2-EN-1-YL)CYCLOHEXANONE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 62, no. 8 (August 19, 2019): 66–70. http://dx.doi.org/10.6060/ivkkt.20196208.5897.

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Recently, vinyl chlorides has been increasingly used as electrophilic partners in various cross-coupling reactions. In contrast to inaccessible and expensive vinyl bromides and iodides, in many cases vinyl chlorides are highly active in the presence of not only traditional palladium complexes, but also economical and safe compounds of iron, cobalt and nickel. Earlier, we reported on the development of new approaches to the getting of stereochemically pure (E)- and (Z)-vinyl chlorides and their successful use at the synthesis of medicines and insect pheromones. Continuing this work, an effective method of the synthesis of (E)- and (Z)-isomers of 2-(3-chloroprop-2-en-1-yl)cyclohexanone - convenient precursors of 2-(alk-2-en-1-yl)cyclohexanones, known flavors and intermediates in the synthesis of polycyclic compounds was developed. In the reaction of ethyl 2-oxocyclohexanecarboxylate with the (E)- and (Z)-isomers of 1,3-dichloropropene under the phase-transfer catalysis conditions in the presence of K2CO3, the corresponding (E)- and (Z)-isomers of ethyl 1-(3-chloroprop-2-en-1-yl)-2-oxocyclohexanecarboxylate were obtained in high yields (80-86%), without allyl rearrangement. The complete retention of the configuration of the chlorovinyl group is observed. Standard methods of the decarboxylation of isomers of ethyl 1-(3-chloroprop-2-en-1-yl)-2-oxocyclohexanecarboxylate under acidic or basic conditions result in very average yields of the corresponding chlorovinyl ketones. The best results were obtained by their decarbalkoxylation in slightly modernized Krapcho conditions. Carrying out reaction in N-methylpyrrolidone at 140-150 °C in the presence of 3 eq. LiCl and 2 eq. of H2O leads to individual (E)- and (Z)-isomers of 2-(3-chloroprop-2-en-1-yl)cyclohexanone in 79-82% yields and a stereochemical purity of ~ 99%. The structure of the obtained compounds were confirmed by HRGC, NMR, and GC/MS data. The configuration of the vinyl group was proved by the coupling constants of the vinyl hydrogens, equal to 13.2-13.4 and 7.0-7.3 Hz for the (E)- and (Z)-products, respectively, as well as by the downfield shift of the allyl carbon atom of trans-isomers by ~4 ppm as compared to the cis-analogs.

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30

Kraka, Elfi, Wenli Zou, Yunwen Tao, and Marek Freindorf. "Exploring the Mechanism of Catalysis with the Unified Reaction Valley Approach (URVA)—A Review." Catalysts 10, no. 6 (June 19, 2020): 691. http://dx.doi.org/10.3390/catal10060691.

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The unified reaction valley approach (URVA) differs from mainstream mechanistic studies, as it describes a chemical reaction via the reaction path and the surrounding reaction valley on the potential energy surface from the van der Waals region to the transition state and far out into the exit channel, where the products are located. The key feature of URVA is the focus on the curving of the reaction path. Moving along the reaction path, any electronic structure change of the reacting molecules is registered by a change in their normal vibrational modes and their coupling with the path, which recovers the curvature of the reaction path. This leads to a unique curvature profile for each chemical reaction with curvature minima reflecting minimal change and curvature maxima, the location of important chemical events such as bond breaking/forming, charge polarization and transfer, rehybridization, etc. A unique decomposition of the path curvature into internal coordinate components provides comprehensive insights into the origins of the chemical changes taking place. After presenting the theoretical background of URVA, we discuss its application to four diverse catalytic processes: (i) the Rh catalyzed methanol carbonylation—the Monsanto process; (ii) the Sharpless epoxidation of allylic alcohols—transition to heterogenous catalysis; (iii) Au(I) assisted [3,3]-sigmatropic rearrangement of allyl acetate; and (iv) the Bacillus subtilis chorismate mutase catalyzed Claisen rearrangement—and show how URVA leads to a new protocol for fine-tuning of existing catalysts and the design of new efficient and eco-friendly catalysts. At the end of this article the pURVA software is introduced. The overall goal of this article is to introduce to the chemical community a new protocol for fine-tuning existing catalytic reactions while aiding in the design of modern and environmentally friendly catalysts.

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31

Sai, Masahiro, Hideki Yorimitsu, and Koichiro Oshima. "ChemInform Abstract: Allyl-, Allenyl-, and Propargyl-Transfer Reactions Through Cleavage of C-C Bonds Catalyzed by an N-Heterocyclic Carbene/Copper Complex: Synthesis of Multisubstituted Pyrroles." ChemInform 42, no. 29 (June 27, 2011): no. http://dx.doi.org/10.1002/chin.201129099.

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32

Hildenbrand, Knut. "The SO4·̄induced Oxidation of 2′-Deoxyuridine-5′-phosphate, Uridine-5′-phosphate and Thymidine-5′-phosphate. An ESR Study in Aqueous Solution." Zeitschrift für Naturforschung C 45, no. 1-2 (February 1, 1990): 47–58. http://dx.doi.org/10.1515/znc-1990-1-210.

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Abstract Reactions of photolytically generated SO4·̄ with 2′-deoxyuridine-5′-phosphate (5′-dUMP), uridine-5′-phosphate (5′-UMP) and thymidine-5′-phosphate (5′-dTMP) were studied by ESR spectroscopy in aqueous solution under anoxic conditions. From 5′-dUMP and 5′-UMP the 5′,5-cyclicphosphate-6-yl radicals 10 and 11 were generated (pH 2 -11) whereas from 5′-dTMP at pH 3 -8 the 5,6-dihydro-6-hydroxy-5-yl radical 14 and at pH 7 -1 1 the 5-methylene-2′-deoxyuridine-5′-phosphate radical 15 was produced. In the experiments with 5′-UMP in addition to radical 11 the signals of sugar radicals 12 and 13 were detected. It is assumed that the base radical cations act as intermediates in the SO4·̄-induced radical reactions. The 5′-phosphate group adds intramolecularly to the C(5)−C(6) bond of the uraclilyl radical cation whereas the thymidyl radical cation of 5′-dTMP reacts with H2O at pH < 8 to yield the 6-OH-5yl adduct 14 deprotonates at pH > 7 thus forming the allyl-type radical 15. In 5′-UMP transfer of the radical site from the base to the sugar moiety competes with intramolecular phosphate addition.

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33

Yoshikai, Naohiko, and Ke Gao. "Cobalt-catalyzed directed alkylation of arenes with primary and secondary alkyl halides." Pure and Applied Chemistry 86, no. 3 (March 20, 2014): 419–24. http://dx.doi.org/10.1515/pac-2014-5005.

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Abstract A cobalt–N-heterocyclic carbene catalyst allows ortho-alkylation of aromatic imines with unactivated primary and secondary alkyl chlorides and bromides under room-temperature conditions. The scope of the reaction encompasses or complements that of cobalt-catalyzed ortho-alkylation reactions with olefins as alkylating agents that we developed previously. Stereochemical outcomes of secondary alkylation reactions suggest that the reaction involves single-electron transfer from a cobalt species to the alkyl halide to generate the corresponding alkyl radical. A cycloalkylated product obtained by this method can be transformed into unique spirocycles through manipulation of the directing group and the cycloalkyl groups.

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34

Griesser, Markus, Jean-Philippe R. Chauvin, and Derek A. Pratt. "The hydrogen atom transfer reactivity of sulfinic acids." Chemical Science 9, no. 36 (2018): 7218–29. http://dx.doi.org/10.1039/c8sc02400f.

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Sulfinic acids are characterized to be very good H-atom donors to each of alkyl and alkoxyl radicals. In order to participate in useful radical chain reactions, the sulfonyl radicals must undergo fast propagating reactions to avoid autoxidation, which is surprisingly rate-limited by the reaction of sulfonyl radicals with oxygen.

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35

Zerk, Timothy J., Lawrence R. Gahan, Elizabeth H. Krenske, and Paul V. Bernhardt. "The fate of copper catalysts in atom transfer radical chemistry." Polymer Chemistry 10, no. 12 (2019): 1460–70. http://dx.doi.org/10.1039/c8py01688g.

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The pathway of atom transfer radical polymerisation (ATRP) is influenced by the nature of the alkyl bromide initiator (RBr) to the extent that reactions between the radical R˙ and the original copper(i) catalyst can divert the reaction toward different products.

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36

Kishore, Ram, Monika Kamboj, and Manisha Shukla. "Triton-B Mediated One-Pot Multicomponent Synthesis of 3,5 Substituted Tetrahydro-2H-1,3,5-Thidiazine-2-Thiones." Oriental Journal of Chemistry 34, no. 6 (November 2, 2018): 2878–83. http://dx.doi.org/10.13005/ojc/340627.

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A new-fangled, proficient, one-pot multi component, intramolecular C-S bond formation reaction, mediated by phase transfer catalyst, Triton-B, is described in this paper. The reaction of alkyl/ phenyl amines, CS2 and formaldehyde catalyzed via Triton-B resulted in formation of 3-(Alkyl or aryl methyl),5-(Alkyl or aryl methyl) substituted tetrahydro-2H-1,3,5-thiadiazine-2-thiones compounds(1a-15a). These compounds (1a-15a) were characterized with the help of elemental analysis, IR, NMR and mass spectroscopic methods. The PTC mediated reactions require mild reaction condition and reduced time period for completion. The reaction is achieved at normal temperature under solvent free conditions with good yields and great selectivity. This methodology discourages the traditional synthesis method of inorganic base for such coupling reaction.

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37

Fantin, Marco, Francesca Lorandi, Armando Gennaro, Abdirisak Isse, and Krzysztof Matyjaszewski. "Electron Transfer Reactions in Atom Transfer Radical Polymerization." Synthesis 49, no. 15 (July 4, 2017): 3311–22. http://dx.doi.org/10.1055/s-0036-1588873.

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Electrochemistry may seem an outsider to the field of polymer science and controlled radical polymerization. Nevertheless, several electrochemical methods have been used to determine the mechanism of atom transfer radical polymerization (ATRP), using both a thermodynamic and a kinetic approach. Indeed, electron transfer reactions involving the metal catalyst, initiator/dormant species, and propagating radicals play a crucial role in ATRP. In this mini-review, electrochemical properties of ATRP catalysts and initiators are discussed, together with the mechanism of the atom and electron transfer in ATRP.1 Introduction2 Thermodynamic and Electrochemical Properties of ATRP Catalysts3 Thermodynamic and Electrochemical Properties of Alkyl Halides and Alkyl Radicals4 Atom Transfer from an Electrochemical and Thermodynamic Standpoint5 Mechanism of Electron Transfer in ATRP6 Electroanalytical Techniques for the Kinetics of ATRP Activation7 Electrochemically Mediated ATRP8 Conclusions

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38

Wiederkehr, Nadir Ana. "REDOX REACTIONS INVOLVING N-ALKYL-DIHYDRONICOTINAMIDES." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2, no. 2 (December 20, 1994): 121–35. http://dx.doi.org/10.48141/sbjchem.v2.n2.1994.122_1994.pdf.

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Electron transfer reactions involving a series of N-alkyl-dihydronicotinamides (R-NAH) as donors were studied in homogenous solvents and in micellar media. In particular, the redox chemistry and kinetics of the reduction of methylene blue and cytochrome-C, by varying the alkyl chain length (R = C4, C8, C12) were investigated The schemes proposed for functionalized surfactants of nicotinamide suggest photochemical conversion based on light-induced electron-transfer reactions.

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39

Köken, Nesrin. "Polymers containing amino bis(methylene phosphonic acid) groups for scale inhibition." Pigment & Resin Technology 48, no. 1 (January 7, 2019): 73–83. http://dx.doi.org/10.1108/prt-01-2017-0007.

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Purpose The purpose of this paper is to prepare poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by two different routes. In the first route, poly(allyl amine-ran-acrylic acid)s were produced by radical copolymerization of a mixture of ally amine and acrylic acid, then converted into poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid]s by the Mannich reaction with a mixture of formaldehyde and phosphonic acid. In the second route, allyl amino bis(methylene phosphonic acid) monomer was synthesized and copolymerised with acrylic acid. The aim of this work is to produce low-molecular-weight copolymer with the low amount of nitrogen and phosphorous having better scale inhibiting performance than commercial low-molecular-weight poly(acrylic acid)s. Design/methodology/approach Poly(allyl amine-ran-acrylic acid)s were prepared by radical copolymerisation of a mixture of ally amine and acrylic acid, and the molecular weight of copolymers was regulated by using an effective chain transfer compound and the formed copolymer was reacted with a mixture of formaldehyde and phosphorous acid. Allyl amino bis(methylene phosphonic acid) monomer was prepared and then copolymerised with acrylic acid using radical initiators. Findings Poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] produced with both routes, especially low-molecular weight ones have better anti-scaling performance than low-molecular-weight commercial poly(acrylic acid). Research limitations/implications By using an excess of formaldehyde and phosphonic acid, a limited increase in the conversion of amine groups of poly(allyl amine-ran-acrylic acid) to amino methylene phosphonic acid groups was achieved, so unreacted amine groups were always present in the structure of the final copolymers. Practical implications The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] may be used as a better anti-scaling polymer in industry. Social implications The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] is an alternative polymer for scale inhibition in the water boilers. Originality/value The low-molecular-weight poly[allyl amino bis(methylene phosphonic acid)-ran-acrylic acid] copolymers containing both carboxylic acid and amino bis(methylene phosphonic acid) are more effective anti-scaling additives than poly(acrylic acid)s in water boilers.

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40

Kimura, Yoshifumi. "Solvation heterogeneity in ionic liquids as demonstrated by photo-chemical reactions." Pure and Applied Chemistry 92, no. 10 (October 25, 2020): 1695–708. http://dx.doi.org/10.1515/pac-2019-1116.

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AbstractIt has been recognised that ionic liquids (ILs) with long alkyl-chains have a segregated structure due to the inhomogeneous distribution of polar parts and non-polar parts. This inhomogeneity of ILs brings about unique solvation phenomena of solute molecules dissolved in ILs. We have investigated various solvation-state selective phenomena by using laser spectroscopic techniques such as solvation state selective vibrational spectroscopy, translational and rotational dynamics of small molecules in ILs, and solvation state selective fundamental chemical reactions. In this paper, we have reviewed an intramolecular electron transfer (ET) reaction in the Marcus inverted region of N,N-dimethyl-p-nitroaniline and an intramolecular proton transfer (IPT) reaction in 4′-N,N-diethylamino-3-hydroxyflavone as examples of chemical reactions affected by unique solvation in ILs.

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41

Mathews, Peggy Jane, and John A. Stone. "Ethyl cation transfer from diethylchloronium to alkyl aromatics studied by high pressure mass spectrometry." Canadian Journal of Chemistry 66, no. 5 (May 1, 1988): 1239–48. http://dx.doi.org/10.1139/v88-202.

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Diethylchloronium (C2H5)2Cl+) has been formed in a high pressure (2–4 Torr) ion source using a C2H5Cl/CH4 mixture. (C2H5)2Cl+ reacts with C2H5Cl (Ea = 22 ± 2 kcal mol−1) at temperatures above 500 K to give [Formula: see text]. The reaction of (C2H5)2Cl+ with B (B = benzene, toluene, isopropylbenzene, mesitylene) yields mainly C2H5B+ at temperatures below 500 K but BH+ is also formed at higher temperatures. The further reactions of C2H5B+ include proton transfer to B yielding BH+ (mesitylene), hydride transfer from B (isopropylbenzene), and reaction with C2H5Cl+ (C2H5)2B+ (toluene and benzene) and (C2H5)3B+ (benzene). The rate constants for the reaction (C2H5)2Cl+ + B → C2H5B+ + C2H5B+ + C2H5Cl increase in the order of increasing reaction exothermicity (mesitylene > isopropylbenzene > toluene > benzene). Mesitylene has a negative temperature coefficient, isopropylbenzene has no temperature coefficient, and toluene and benzene show positive temperature coefficients of reaction rate constants consistent with the double well potential theory for gas phase SN2 reactions.

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42

Lin, Cheng-Tung, and Wen-Jei Hsu. "Study of trichloronitrosomethane: regioselective cycloadditions of 2-substituted-1,3-butadienes." Canadian Journal of Chemistry 67, no. 12 (December 1, 1989): 2153–61. http://dx.doi.org/10.1139/v89-335.

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The regioselectivity of cycloaddition reactions of trichloronitrosomethane (1) with 2-alkyl (R = Me, Et, i-Pr, t-Bu, CF3, Bz, and Cl) and 2-aryl (Ar = Ph, 4-CH3OPh, 4-CH3Ph, 3-CH3Ph, and 4-ClPh) 1,3-butadienes is described. The orientation of cycloaddition is substituent dependent, producing 2,5-disubstituted (para) and 2,4-disubstituted (meta) 3,6-dihydro-1,2-oxazines from 2-alkyl- and 2-aryl-1,3-butadienes respectively. Increasing the bulk of the substituent from methyl to tert-butyl in 2-alkyl-1,3-butadienes increases the regioselectivity. Kinetic studies in various solvents indicate that plots of log km/kH vs. Hammett σ+ values give straight lines with the ρ values lying between −0.60 and −0.91 for the reactions with 2-aryl-1,3-butadienes. A concerted reaction mechanism is proposed and the orientation preference is consistent with frontier molecular orbital predictions for 2-alkyl-1,3-butadienes. In the reactions with 2-aryl-1,3-butadienes, a transition state leading to a spin-paired diradical, which then converts by partial electron transfer to zwitterionic structure, is proposed. Keywords: trichloronitrosomethane, 3,6-dihydro-1,2-oxazine, regioselectivity, [2 + 4] cycloaddition.

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43

Kerscher, Thomas, Shahram Mihan, and Wolfgang Beck. "Addition of Organometallic Nucleophiles (Carbonylmetallates) to the Allyl Ligand of [(η3-C3H5)Pd(μ-Cl)]2. Synthesis and Structure of (η3-C3H5)Mn(CO)3PEt3." Zeitschrift für Naturforschung B 66, no. 8 (August 1, 2011): 861–64. http://dx.doi.org/10.1515/znb-2011-0813.

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The reaction of the organometallic nucleophile [Mn(CO)4- PEt3]− at the allyl ligand of [(η3-C3H5)Pd(μ-Cl)]2 proceeds by allyl transfer from Pd(II) to Mn(-I) to give [(η3-C3H5)- Mn(CO)3PEt3], of which the structure has been determined by X-ray diffraction.

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44

Yao, Hongjun, Wenfei Hu, and Wei Zhang. "Difunctionalization of Alkenes and Alkynes via Intermolecular Radical and Nucleophilic Additions." Molecules 26, no. 1 (December 28, 2020): 105. http://dx.doi.org/10.3390/molecules26010105.

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Popular and readily available alkenes and alkynes are good substrates for the preparation of functionalized molecules through radical and/or ionic addition reactions. Difunctionalization is a topic of current interest due to its high efficiency, substrate versatility, and operational simplicity. Presented in this article are radical addition followed by oxidation and nucleophilic addition reactions for difunctionalization of alkenes or alkynes. The difunctionalization could be accomplished through 1,2-addition (vicinal) and 1,n-addition (distal or remote) if H-atom or group-transfer is involved in the reaction process. A wide range of moieties, such as alkyl (R), perfluoroalkyl (Rf), aryl (Ar), hydroxy (OH), alkoxy (OR), acetatic (O2CR), halogenic (X), amino (NR2), azido (N3), cyano (CN), as well as sulfur- and phosphorous-containing groups can be incorporated through the difunctionalization reactions. Radicals generated from peroxides or single electron transfer (SET) agents, under photoredox or electrochemical reactions are employed for the reactions.

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45

Chen, Sisi, Ming Liu, Jiandong Zhang, Zhengbiao Zhang, Jian Zhu, Xiangqiang Pan, and Xiulin Zhu. "Photoresponsive dynamic covalent bond based on addition–fragmentation chain transfer of allyl selenides." Polymer Chemistry 12, no. 11 (2021): 1622–26. http://dx.doi.org/10.1039/d0py01730b.

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46

Tabanelli, Tommaso, Paola Blair Vásquez, Emilia Paone, Rosario Pietropaolo, Nikolaos Dimitratos, Fabrizio Cavani, and Francesco Mauriello. "Improved Catalytic Transfer Hydrogenation of Levulinate Esters with Alcohols over ZrO2 Catalyst." Chemistry Proceedings 2, no. 1 (November 9, 2020): 28. http://dx.doi.org/10.3390/eccs2020-07585.

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Levulinic acid (LA) and its esters (alkyl levulinates) are polyfunctional molecules that can be obtained from lignocellulosic biomass. Herein, the catalytic conversion of methyl and ethyl levulinates into γ-valerolactone (GVL) via catalytic transfer hydrogenation (CTH) by using methanol, ethanol, and 2-propanol as the H-donor/solvent, was investigated under both batch and gas-flow conditions. In particular, high-surface-area, tetragonal zirconia has proven to be a suitable catalyst for this reaction. Isopropanol was found to be the best H-donor under batch conditions, with ethyl levulinate providing the highest yield in GVL. However, long reaction times and high autogenic pressures are needed in order to work in the liquid-phase at high temperature with light alcohols. The reactions occurring under continuous gas-flow conditions, at atmospheric pressure and a relatively low contact time (1 s), were found to be much more efficient, also showing excellent GVL yields when EtOH was used as the reducing agent (GVL yield of around 70% under optimized conditions). The reaction has also been tested using a true bio-ethanol, derived from agricultural waste. These results represent the very first examples of the CTH of alkyl levulinates under continuous gas-flow conditions reported in the literature.

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47

Bochmann, Manfred, Simon J. Lancaster, Mark D. Hannant, Antonio Rodriguez, Mark Schormann, Dennis A. Walker, and Timothy J. Woodman. "Role of B(C6F5)3 in catalyst activation, anion formation, and as C6F5 transfer agent." Pure and Applied Chemistry 75, no. 9 (January 1, 2003): 1183–95. http://dx.doi.org/10.1351/pac200375091183.

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The versatile reactivity of B(C6F5)3 in alkene polymerization reactions is summarized. Adduct formation with basic anions such as CN– and NH2– gives extremely weakly co- ordinating diborates, which are the basis of some of the most active polymerization catalysts known to date. By contrast, the reaction of B(C6F5)3 with zirconium half-sandwich complexes leads to extensive C6F5 transfer, including the surprising formation of borole-bridged triple decker complexes. Main group alkyls undergo such C6F5 exchange reactions very readily unless donor ligands are present. Borate salts of new three-coordinate zinc alkyl cations proved to be highly effective catalysts for the ring-opening polymerization of epoxides and lactones.

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48

Weidner, Karin, and Philippe Renaud. "Kinetic Study of the Radical Azidation with Sulfonyl Azides." Australian Journal of Chemistry 66, no. 3 (2013): 341. http://dx.doi.org/10.1071/ch12523.

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Rate constants for the reaction between a secondary alkyl radical and two different sulfonyl azides were determined using bimolecular competing radical reactions. The rates of azidation were determined by competition with hydrogen atom transfer from tris(trimethylsilyl)silane ((TMS)3SiH) of the 4-phenylcyclohexyl radical. 3-Pyridinesulfonyl azide and trifluoromethanesulfonyl azide were found to have rate constants for azidation of 2 × 105 M–1 s–1 and 7 × 105 M–1 s–1 at 80°C, respectively.

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49

Guthrie, J. Peter, Leonardo Leandro, and Vladimir Pitchko. "Elimination reactions Calculation of rate constants from equilibrium constants and distortion energies by means of no barrier theory." Canadian Journal of Chemistry 83, no. 9 (September 1, 2005): 1654–66. http://dx.doi.org/10.1139/v05-160.

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No barrier theory has been applied to the E2 reactions of five alkyl bromides with ethanolic ethoxide. The model used for these reactions is that the reaction proceeds from the encounter complex of base and alkyl halide to the product encounter complex of halide ion and alkene (and alcohol), and requires five simple processes, which combine to give the concerted elimination: transfer of a proton from carbon to base; a change in geometry at the carbon which loses a proton from sp3 to sp2; breaking the C-leaving group bond; a change in geometry at the carbon which loses the leaving group from sp3 to sp2; and a change in the length of the carboncarbon bond. The free energy of activation can be calculated with an rms error of 2.58 kcal mol1 (1 cal = 4.184 J).Key words: Elimination, no barrier theory, rate constant, equilibrium constant.

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50

Vasu, Dhananjayan, Samir Kundlik Pawar, and Rai-Shung Liu. "Gold-catalyzed cyclization of allenyl acetal derivatives." Beilstein Journal of Organic Chemistry 9 (August 27, 2013): 1751–56. http://dx.doi.org/10.3762/bjoc.9.202.

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The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our deuterium labeling experiments supports a 1,4-hydride shift of the resulting allyl cationic intermediates because a complete deuterium transfer is observed. We tested the reaction on various acetal substrates bearing a propargyl acetate, giving 4-methoxy-5-alkylidenecyclopent-2-en-1-ones 4 via a degradation of the acetate group at the allyl cation intermediate.

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