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Journal articles on the topic 'Cyclopropanation reaction'

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Published: 9 March 2023

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1

Calter, Michael A. "Transition Metal-Catalyzed, Asymmetric Reactions of Diazo Compounds." Current Organic Chemistry 1, no. 1 (May 1997): 37–70. http://dx.doi.org/10.2174/1385272801666220121184444.

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The past ten years have seen impressive advances in asymmetric synthesis. This review summarizes the recent advances in a particular set of asymmetric reactions, the reactions of diazo compounds catalyzed by transition metal complexes. Additionally, the emphasis of this summary is on reactions wherein the induction arises from a catalyst or an auxiliary, rather than some inherent asymmetry of the substrate. The covered reactions fall into two reaction types; cyclopropanations and insertions. The cyclopropanation section of this review describes how high stereoselectivities are possible using either chiral auxiliaries or various metal complexes. Both these strategies are effective for producing optically-enriched intermediates; however, the use of catalysts to control the stereochemistry of the cyclopropanation reaction is much more common than the corresponding use of auxiliaries Workers in the asymmetric cyclopropanation field have primarily used Cu(l) and Rh(ll) complexes as catalysts for these reactions, although several complexes of other metals do afford high asymmetric induction. Both inter- and intramolecular cyclopropanations afford synthetically useful selectivities. The insertion section of this review summarizes recent advances in the use of auxiliaries and catalysts for controlling the stereoselectivity of the insertion into various bonds. Insertion into C-H bonds are by far the most intensively studied, although there has been some success with asymmetric insertions into 0-H, S-H, Si-H and C-0 bonds. Complexes of Rh(ll) are almost universally employed for asymmetric insertions. As in the case of cyclopropanations, both inter- and intramolecular insertions can proceed with useful selectivities. Again, catalyst control has proven a more versatile way to control absolute stereochemistry than auxiliary control.

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2

ZHAO, CUNYUAN, DONG-QI WANG, and DAVID LEE PHILLIPS. "DENSITY FUNCTIONAL STUDY OF SELECTED MONO-ZINC AND GEM-DIZINC RADICAL CARBENOID CYCLOPROPANATION REACTIONS: OBSERVATION OF AN EFFICIENT RADICAL ZINC CARBENOID CYCLOPROPANATION REACTION AND THE INFLUENCE OF THE LEAVING GROUP ON RING CLOSURE." Journal of Theoretical and Computational Chemistry 02, no. 03 (September 2003): 357–69. http://dx.doi.org/10.1142/s0219633603000549.

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We report a theoretical study of the cyclopropanation reactions of EtZnCHI, (EtZn)2CH EtZnCHZnI, and EtZnCIZnI radicals with ethylene. The mono-zinc and gem-dizinc radical carbenoids can undergo cyclopropanation reactions with ethylene via a two-step reaction mechanism similar to that previously reported for the CH2I and IZnCH2 radicals. The barrier for the second reaction step (ring closure) was found to be highly dependent on the leaving group of the cyclopropanation reaction. In some cases, the (di)zinc carbenoid radical undergoes cyclopropanation via a low barrier of about 5–7 kcal/mol on the second reaction step and this is lower than the CH2I radical reaction which has a barrier of about 13.5 kcal/mol for the second reaction step. Our results suggest that in some cases, zinc radical carbenoid species have cyclopropanation reaction barriers that can be competitive with their related molecular Simmons-Smith carbenoid species reactions and produce somewhat different cyclopropanated products and leaving groups.

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3

Shintani, Ryo, Ayase Ohzono, and Kentaro Shirota. "Phosphinative cyclopropanation of allyl phosphates with lithium phosphides." Chemical Communications 56, no. 79 (2020): 11851–54. http://dx.doi.org/10.1039/d0cc04854b.

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A new cyclopropanation reaction of allyl phosphates with lithium phosphides has been developed to give cyclopropylphosphines, and high selectivity toward cyclopropanation has been realized by conducting the reaction in the presence of HMPA.

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4

Pyne, Stephen G., Karl Schafer, Brian W. Skelton, and Allan H. White. "Asymmetric Synthesis of Protected 2-Substituted Cyclopropane Amino Acids." Australian Journal of Chemistry 51, no. 2 (1998): 127. http://dx.doi.org/10.1071/c97105.

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The cyclopropanation reactions of (1a) with ethyl and t-butyl (dimethylsulfuranylidene)acetate proceeded with good diastereoselectivity and resulted in the formation of three diastereoisomeric products. The major diastereoisomeric product ((2a) and (2b), respectively) could be isolated in pure form by simple recrystallization. The stereochemistry of the major cyclopropane product (2b) has been determined by single-crystal X-ray structural analysis. These cyclopropanation products were susceptible to ring opening of the cyclopropane ring upon reduction with sodium borohydride or acid hydrolysis. The reaction of (1b) with ethyl (dimethylsulfuranylidene)acetate gave a mixture of four diastereoisomeric cyclopropanation products. The reactions of (1a) and (1b) with the sulfur ylide derived from 3-methoxycarbonylallyldimethylsulfonium bromide were less successful in terms of product diastereoselectivities.

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5

Davies, Huw M. L. "Rhodium-Stabilized Vinylcarbenoid Intermediates in Organic Synthesis." Current Organic Chemistry 2, no. 5 (September 1998): 463–88. http://dx.doi.org/10.2174/1385272802666220128232502.

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Abstract: This article will give an overview of the reactions and synthetic utility of rhodium-stabilized vinylcarbenoids, which have been shown in recent years to be versatile synthetic intermediates. They undergo highly diastereoselective cyclopropanations with a wide array of alkenes and dienes, and the resulting vinylcyclopropanes are readily converted to other ring systems. Most notable is the reaction between vinylcarbenoids and dienes, which is a general method for the stereoselective construction of seven-membered carbocycles by means of a tandem cyclopropanation/Cope rearrangement sequence. Efficient insertions into Si-H, C-H, N-H and 0-H bonds can also be achieved by rhodium-stabilized vinylcarbenoids. The synthetic utility of vinylcarbenoid chemistry has been greatly enhanced by the recent development of chiral catalysts and auxiliaries that enable this chemistry to be achieved with high asymmetric induction.

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6

Cressy, Derek, Cristian Zavala, Anthony Abshire, William Sheffield, and Ampofo Darko. "Tuning Rh(ii)-catalysed cyclopropanation with tethered thioether ligands." Dalton Transactions 49, no. 44 (2020): 15779–87. http://dx.doi.org/10.1039/d0dt03019h.

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7

Herraiz, Ana G., and Marcos G. Suero. "New Alkene Cyclopropanation Reactions Enabled by Photoredox Catalysis via Radical Carbenoids." Synthesis 51, no. 14 (June 11, 2019): 2821–28. http://dx.doi.org/10.1055/s-0037-1611872.

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We describe the recent emergence of a new approach for the synthesis of cyclopropane rings by means of photoredox catalysis. This methodology relies on the photocatalytic generation of radical carbenoids or carbenoid-like radicals as cyclopropanating species, and is characterized by excellent functional group tolerance, chemoselectivity and the ability to form cyclopropanes with excellent control from E/Z alkene mixtures. The mild reaction conditions and employment of user-friendly reagents are highly attractive features that may lead to this approach being used in academic and industrial laboratories.1 Introduction2 Photoredox-Catalyzed Alkene Cyclopropanations with Radical Carbenoids3 Conclusions and Outlook

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8

Lorecchio, Chiara, Emanuela Tamburri, Laura Lazzarini, Silvia Orlanducci, Robertino Zanoni, and Pietro Tagliatesta. "Covalent Functionalization of Nanodiamonds by Ruthenium Porphyrin, and Their Catalytic Activity in the Cyclopropanation Reaction of Olefins." Catalysts 10, no. 6 (June 13, 2020): 666. http://dx.doi.org/10.3390/catal10060666.

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Detonation nanodiamonds (DNDs) were functionalized by ruthenium porphyrins and used as catalysts in the cyclopropanation reaction of olefins. The heterogeneous catalyst was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and XPS (X-ray photoelectron spectroscopy). The XPS was used to control the binding of the ruthenium porphyrin to the DNDs’ surface. This catalyst was used in the cyclopropanation reactions of simple olefins and was reused with no loss of activity in four consecutive cycles, after recovering each time by simple centrifugation.

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9

Papageorgiou, Charles D., Steven V. Ley, and Matthew J. Gaunt. "Organic-Catalyst-Mediated Cyclopropanation Reaction." Angewandte Chemie International Edition 42, no. 7 (February 17, 2003): 828–31. http://dx.doi.org/10.1002/anie.200390222.

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10

Bremeyer, Nadine, Stephen C. Smith, Steven V. Ley, and Matthew J. Gaunt. "An Intramolecular Organocatalytic Cyclopropanation Reaction." Angewandte Chemie International Edition 43, no. 20 (May 10, 2004): 2681–84. http://dx.doi.org/10.1002/anie.200454007.

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11

Bremeyer, Nadine, Stephen C. Smith, Steven V. Ley, and Matthew J. Gaunt. "An Intramolecular Organocatalytic Cyclopropanation Reaction." Angewandte Chemie 116, no. 20 (May 10, 2004): 2735–38. http://dx.doi.org/10.1002/ange.200454007.

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12

Krasnova, Larissa B., and Andrei K. Yudin. "Novel nitrogen containing chelating ligands from aziridines Preparation, coordination studies, and catalytic application in the cyclopropanation of styrene." Canadian Journal of Chemistry 83, no. 6-7 (June 1, 2005): 1025–32. http://dx.doi.org/10.1139/v05-113.

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Novel ligands have been synthesized by the reaction of readily available aziridines with appropriate nitrogen based nucleophiles under mild conditions. Complexes of different stoichiometry can be readily obtained upon reaction between these ligands and the corresponding copper salts. The enantiomerically pure form of one of the ligands was obtained and applied in the styrene cyclopropanation reaction, where the copper catalyst revealed unexpectedly high diastereoselectivity in comparison with the known systems.Key words: ligands, aziridines, cyclopropanation, copper catalysts, metal complexes.

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13

Shen, Guang Huan, and Joon Hee Hong. "Chemical Synthesis of Acyclic Nucleoside Phosphonate Analogs Linked with Cyclic Systems between the Phosphonate and the Base Moieties." Current Medicinal Chemistry 27, no. 35 (October 29, 2020): 5918–48. http://dx.doi.org/10.2174/0929867326666190620100217.

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The syntheses of acyclic nucleoside phosphonate (ANP) analogs linked with cyclic systems are described in the present review. The purpose of the review is to report the methodology of ANP analogs and to give an idea on the synthesis of a therapeutic structural feature of such analogs. The cyclopropane systems were mainly prepared by diazomethane cyclopropanation catalyzed by Pd(OAc)2, intramolecular alkylation, Kulinkovich cyclopropanation, and use of difluorocyclopropane, and so forth. The preparation of methylenecyclopropane system was made by diazoacetate cyclopropanation catalyzed by Rhodium followed by addition-elimination reactions. For the preparation of a variety of tethered 1,2,3-triazole systems, 1,3-dipolar cycloaddition between azidealkylphosphonates and propargylated nucleobases was mainly applied. The formation of various phosphonate moieties was achieved via phosphonylation of alkoxide, cross-coupling between BrZnCF2P (O)(OEt)2 with iodoalkens catalyzed by CuBr, Michaelis-Arbuzov reaction with phosphite, and Rh(II)-catalyzed O-H insertion, and so forth.

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14

Charette, André B., and Jean-Emmanuel Bouchard. "Catalytic asymmetric synthesis of cyclopropylphosphonates Catalysts' scope and reactivity." Canadian Journal of Chemistry 83, no. 6-7 (June 1, 2005): 533–42. http://dx.doi.org/10.1139/v05-074.

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The transition metal-catalyzed cyclopropanation of alkenes using α-diazomethylphosphonates leads to cyclopropylphosphonate derivatives in high yields. The reaction proceeds well with copper, rhodium, and ruthenium catalysts. The best catalysts for the enantioselective version are either Evans' Cu·bis(oxazoline) or Nishiyama's Ru·pybox.Key words: cyclopropylphosphonic acids, copper catalysts, ruthenium catalysts, cyclopropanation, diazo reagents.

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15

Allouche, Emmanuelle M. D., and André B. Charette. "Cyclopropanation Reactions of Semi-stabilized and Non-stabilized Diazo Compounds." Synthesis 51, no. 21 (September 23, 2019): 3947–63. http://dx.doi.org/10.1055/s-0037-1611915.

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The cyclopropane ring is present in a large number of bioactive molecules as its incorporation often greatly alters their physiochemical properties. The synthesis of such motif is therefore of interest. Diazo compounds are versatile and powerful reagents that can be used in a broad range of reactions, including cyclopropanation processes. However, in case of unstable diazo reagents such as the donor-substituted variants, their inherent toxicity and instability have hampered their effective synthesis and utilization. Herein, we report the recent advances devoted to the safe and facile production of these potentially hazardous species and their subsequent application in cyclopropanation reactions, allowing the synthesis of more complex cyclopropylated motifs.1 Introduction2 Halomethylmetal-Mediated Cyclopropanations3 Cyclopropanations through Metallic- or Free Carbenes3.1 Transition-Metal-Catalyzed Decomposition of Diazo Compounds3.2 Metal-Free Decomposition of Diazo Compounds4 Michael Induced Ring Closure (MIRC) Reactions4.1 Sulfur Ylides4.2 1,3-Dipolar Cycloadditions5 Conclusion

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16

Mandour, Hamada S. A., Yoko Nakagawa, Masaya Tone, Hayato Inoue, Nansalmaa Otog, Ikuhide Fujisawa, Soda Chanthamath, and Seiji Iwasa. "Reusable and highly enantioselective water-soluble Ru(II)-Amm-Pheox catalyst for intramolecular cyclopropanation of diazo compounds." Beilstein Journal of Organic Chemistry 15 (February 6, 2019): 357–63. http://dx.doi.org/10.3762/bjoc.15.31.

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A reusable and highly enantioselective catalyst for the intramolecular cyclopropanation of various diazo ester and Weinreb amide derivatives was developed. The reactions catalyzed by a water-soluble Ru(II)-Amm-Pheox catalyst proceeded smoothly at room temperature, affording the corresponding bicyclic cyclopropane ring-fused lactones and lactams in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee). After screening of various catalysts, the Ru(II)-Amm-Pheox complex having an ammonium group proved to be crucial for the intramolecular cyclopropanation reaction in a water/ether biphasic medium. The water-soluble catalyst could be reused at least six times with little loss in yield and enantioselectivity.

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17

Bespalova, N. B., M. A. Bovina, A. I. Rebrov, and M. B. Sergeeva. "Cyclopropanation of buckminsterfullerenevia olefin metathesis reaction." Russian Chemical Bulletin 45, no. 5 (May 1996): 1255–56. http://dx.doi.org/10.1007/bf01431639.

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18

del Hoyo, Ana M., Ana G. Herraiz, and Marcos G. Suero. "A Stereoconvergent Cyclopropanation Reaction of Styrenes." Angewandte Chemie International Edition 56, no. 6 (February 2017): 1610–13. http://dx.doi.org/10.1002/anie.201610924.

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19

del Hoyo, Ana M., Ana G. Herraiz, and Marcos G. Suero. "A Stereoconvergent Cyclopropanation Reaction of Styrenes." Angewandte Chemie 129, no. 6 (December 16, 2016): 1632–35. http://dx.doi.org/10.1002/ange.201610924.

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20

Østby, Runa Berg, Terje Didriksen, Simen Gjelseth Antonsen, Steinar Sollien Nicolaisen, and Yngve Stenstrøm. "Two-Phase Dibromocyclopropanation of Unsaturated Alcohols Using Flow Chemistry." Molecules 25, no. 10 (May 19, 2020): 2364. http://dx.doi.org/10.3390/molecules25102364.

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Dibromocyclopropanations are conventionally done by addition of dibromocarbene to alkenes under phase-transfer conditions in batch reactions using a strong base (50% NaOH (aq)), vigorous stirring and long reaction times. We have shown that cyclopropanation of unsaturated alcohols can be done under ambient conditions using continuous flow chemistry with 40% (w/w) NaOH (aq) as the base. The reactions were generally rapid; the yields were comparable to yields reported in the literature for the conventional batch reaction

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21

Matsumoto, Kouichi, Yuta Hayashi, Kengo Hamasaki, Mizuki Matsuse, Hiyono Suzuki, Keiji Nishiwaki, and Norihito Kawashita. "Electrogenerated base-promoted cyclopropanation using alkyl 2-chloroacetates." Beilstein Journal of Organic Chemistry 18 (August 29, 2022): 1116–22. http://dx.doi.org/10.3762/bjoc.18.114.

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The electrochemical reduction conditions of the reaction of alkyl 2-chloroacetates in Bu4NBr/DMF using a divided cell equipped with Pt electrodes to produce the corresponding cyclopropane derivatives in moderate yields were discovered. The reaction conditions were optimized, the scope and limitations, as well as scale-up reactions were investigated. The presented method for the electrochemical production of cyclopropane derivatives is an environmentally friendly and easy to perform synthetic procedure.

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22

Bostick, TM, SD Christie, TJ Connolly, S. Copp, RF Langler, DL Reid, and M. Zaworotko. "A Novel Cyclopropanation." Australian Journal of Chemistry 49, no. 2 (1996): 243. http://dx.doi.org/10.1071/ch9960243.

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Reaction between benzaldehyde and methyl α- benzylsulfonylacetate furnishes methyl (E)-α- benzylsulfonyl-β-phenylacrylate as the exclusive Knoevenagel adduct. The related condensations between α-benzylsulfonylacetonitrile and paraformaldehyde furnish trans-1-benzylsulfonyl-2-phenylcyclopropane-1-carbonitrile in modest yields. These product structures are established by X-ray crystallographic analysis. Phenylsulfene is ruled out as an intermediate in the formation of the cyclopropane.

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23

Mao, Jiangang, Shuo-Qing Zhang, Bing-Feng Shi, and Weiliang Bao. "Palladium(0)-catalyzed cyclopropanation of benzyl bromides via C(sp3)–H bond activation." Chem. Commun. 50, no. 28 (2014): 3692–94. http://dx.doi.org/10.1039/c3cc49231a.

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24

Lund, Elizabeth A., Isaac A. Kennedy, and Alex G. Fallis. "Dihydrofurans from α-diazoketones due to facile ring opening – cyclization of donor–acceptor cyclopropane intermediates." Canadian Journal of Chemistry 74, no. 12 (December 1, 1996): 2401–12. http://dx.doi.org/10.1139/v96-269.

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A series of α-diazoketones, 8, 25, 28, 31, and 34, have been synthesized and their reaction with ethyl vinyl ether examined under various reaction conditions. In the presence of metal salts (Rh2(OAc)4, Pd(OAc)2, CuCl) the ethoxy-dihydrofurans 12, 37, 39, 41, and 43 are produced. Sensitized irradiation of the α-diazoketone 8 afforded the dihydrofuran 12 plus cyclobutanone 7, while direct photolysis of α-diazoketones 8, 25, 28, 31, and 34 gave the cyclobutanones 7, 38,40,42, and 44, respectively. A sample of the cyclopropylketone 45 was isolated from the rhodium(II) acetate mediated reaction of 34 and its facile rearrangement to dihydrofuran 43 demonstrated. Collectively, these results indicate that the initial product from the reaction of an α-diazoketone with an electron-rich alkene such as ethyl vinyl ether is a cyclopropylketone. The donnor–acceptor substitution pattern of this intermediate results in spontaneous rearrangement to a dihydrofuran. Thus a direct dipolar cycloaddition mechanism is not involved when α-diazoketones react with enol ethers under metal-mediated conditions. Instead, these reactions follow a cyclopropanation rearrangement or, more accurately, cyclopropanation – ring opening – cyciization pathway. Key words: diazoketone, rhodium acetate, dihydrofuran, cyclopropylketone, vinyl ether.

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25

Zhuo, Chun-Xiang, and Jia-Le Wang. "Catalytic Deoxygenative Cyclopropanation of 1,2-Dicarbonyl or Monocarbonyl Compounds via Molybdenum Catalysis." Synlett 33, no. 07 (November 13, 2021): 599–608. http://dx.doi.org/10.1055/a-1696-4553.

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AbstractThe cyclopropanation of alkenes through the transition-metal-catalyzed decomposition of diazo compounds is a powerful and straightforward strategy to produce cyclopropanes. Nevertheless, the appeal of further application of this strategy is tempered by the potentially explosive nature of the diazo substrates. Therefore, it is highly desirable to develop sustainable and operationally safe surrogates for diazo compounds. In this Synpacts article, we discuss recent advances on the cyclopropane syntheses through the catalytic cyclopropanation of alkenes and metal carbenes generated in situ from nondiazo precursors as well as highlight our recent progress on the unprecedented molybdenum-catalyzed deoxygenative cyclopropanation reaction of 1,2-dicarbonyl or monocarbonyl compounds.

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26

Lee, Jiyoun, Donguk Ko, Hyunju Park, and Eun Jeong Yoo. "Direct cyclopropanation of activated N-heteroarenes via site- and stereoselective dearomative reactions." Chemical Science 11, no. 6 (2020): 1672–76. http://dx.doi.org/10.1039/c9sc06369b.

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27

Chi, Yongjian, Lihua Qiu, and Xinfang Xu. "Highly enantioselective synthesis of spirocyclopropyloxindoles via a Rh(ii)-catalyzed asymmetric cyclopropanation reaction." Organic & Biomolecular Chemistry 14, no. 44 (2016): 10357–61. http://dx.doi.org/10.1039/c6ob02160c.

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28

Edulji, S. K., and S. T. Nguyen. "Substrate scope in the olefin cyclopropanation reaction catalyzed by m-oxo-bis[(salen)iron(III)] complexes." Pure and Applied Chemistry 76, no. 3 (January 1, 2004): 645–49. http://dx.doi.org/10.1351/pac200476030645.

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The cyclopropanation of various alkenes with different diazoester compounds was investigated using two different μ-oxo-bis[(salen)iron(III)] complexes, [Fe(3,3',5,5'-tBu4salen)]2O and [Fe(salen)]2O. Ethyl diazoacetate (EDA), tert-butyl diazoacetate (tBDA), and ethyl diazoacetoacetate (EDAA) were used with mono- and disubstituted terminal olefins (styrene and 1,1-diphenyl ethylene, respectively), internal olefin (trans-β-methyl styrene), and an electron-rich alkene (n-butyl vinyl ether). Moderate-to-good cyclopropanation yields were obtained for most substrates.

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29

Rull, Silvia G., Andrea Olmos, and Pedro J. Pérez. "Gold-catalyzed ethylene cyclopropanation." Beilstein Journal of Organic Chemistry 15 (January 7, 2019): 67–71. http://dx.doi.org/10.3762/bjoc.15.7.

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Ethylene can be directly converted into ethyl 1-cyclopropylcarboxylate upon reaction with ethyl diazoacetate (N2CHCO2Et, EDA) in the presence of catalytic amounts of IPrAuCl/NaBArF 4 (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene; BArF 4 = tetrakis(3,5-bis(trifluoromethyl)phenyl)borate).

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30

Szabo, Zita, Sophia Ben Ahmed, Zoltan Nagy, Attila Paczal, and Andras Kotschy. "Enantioselective Cyclopropanation Catalyzed by Gold(I)-Carbene Complexes." Molecules 27, no. 18 (September 7, 2022): 5805. http://dx.doi.org/10.3390/molecules27185805.

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The formation of polysubstituted cyclopropane derivatives in the gold(I)-catalyzed reaction of olefins and propargylic esters is a potentially useful transformation to generate diversity, therefore any method in which its stereoselectivity could be controlled is of significant interest. We prepared and tested a series of chiral gold(I)-carbene complexes as a catalyst in this transformation. With a systematic optimization of the reaction conditions, we were able to achieve high enantioselectivity in the test reaction while the cis:trans selectivity of the transformation was independent of the catalyst. Using the optimized conditions, we reacted a series of various olefins and acetylene derivatives to find that, although the reactions proceeded smoothly and the products were usually isolated in good yield and with good to exclusive cis selectivity, the observed enantioselectivity varied greatly and was sometimes moderate at best. We were unable to establish any structure-property relationship, which suggests that for any given reagent combination, one has to identify individually the best catalyst.

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31

Mikołajczyk, Marian. "Asymmetric cyclopropanation of chiral (1-phosphoryl)vinyl sulfoxides: A new approach to constrained analogs of biologically active compounds." Pure and Applied Chemistry 77, no. 12 (January 1, 2005): 2091–98. http://dx.doi.org/10.1351/pac200577122091.

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This account outlines the results obtained in the author's laboratory on the asymmetric cyclopropanation of enantiopure 1-phosphorylvinyl p-tolyl sulfoxides with sulfur ylides and diazoalkanes. Based on experimental results and theoretical calculations, the transition-state model for asymmetric cyclopropanation is proposed. A great synthetic value of the reaction investigated is exemplified by the total synthesis of constrained analogs of bioactive compounds, namely, enantiopure cyclic analog of phaclofen and cyclopropylphosphonate analogs of nucleotides.

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32

Herraiz, Ana G., and Marcos G. Suero. "A transition-metal-free & diazo-free styrene cyclopropanation." Chemical Science 10, no. 40 (2019): 9374–79. http://dx.doi.org/10.1039/c9sc02749a.

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33

Padwa, Albert, Thomas J. Wisnieff, and Edward J. Walsh. "Intramolecular cyclopropanation reaction of furanyl diazo ketones." Journal of Organic Chemistry 54, no. 2 (January 1989): 299–308. http://dx.doi.org/10.1021/jo00263a009.

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34

Becalski, Adam, William R. Cullen, Michael D. Fryzuk, Georg Herb, Brian R. James, James P. Kutney, Krystyna Piotrowska, and Dianne Tapiolas. "The chemistry of thujone. XII. The synthesis of pyrethroid analogues via chiral cyclopropanation." Canadian Journal of Chemistry 66, no. 12 (December 1, 1988): 3108–15. http://dx.doi.org/10.1139/v88-479.

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An extensive study involving achiral and chiral cyclopropanation of various isoprenoid units derived from the monoterpene thujone is presented. Carbenoid intermediates generated from ethyl and L-menthyl diazoacetates and various achiral and chiral copper catalysts are employed to achieve the desired cyclopropanation reaction. It is shown that high levels of enantiomeric excess can be achieved, particularly when L-menthyl diazoacetate and a chiral catalyst are employed. The resultant products are then converted to pyrethroid-like analogues.

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35

Heinz, Werner R., Raphael Junk, Iker Agirrezabal-Telleria, Bart Bueken, Hana Bunzen, Thorsten Gölz, Mirza Cokoja, Dirk De Vos, and Roland A. Fischer. "Thermal defect engineering of precious group metal–organic frameworks: impact on the catalytic cyclopropanation reaction." Catalysis Science & Technology 10, no. 23 (2020): 8077–85. http://dx.doi.org/10.1039/d0cy01479f.

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36

Buchcic-Szychowska, Aleksandra, Justyna Adamczyk, Lena Marciniak, Adam Marek Pieczonka, Anna Zawisza, Stanisław Leśniak, and Michał Rachwalski. "Efficient Asymmetric Simmons-Smith Cyclopropanation and Diethylzinc Addition to Aldehydes Promoted by Enantiomeric Aziridine-Phosphines." Catalysts 11, no. 8 (August 13, 2021): 968. http://dx.doi.org/10.3390/catal11080968.

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During an implementation of current research, a set of optically pure chiral aziridines and aziridine imines bearing a phosphine moiety was prepared with high values of chemical yield. The above chiral heteroorganic derivatives were tested for catalytic utility as chiral ligands in asymmetric Simmons-Smith cyclopropanation and asymmetric diethylzinc addition to various aldehydes. Most of the desired products were formed in high chemical yields, with satisfactory values of enantiomeric excess (sometimes more than 90%) and diastereomeric ratios (in case of cyclopropanation reaction).

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37

Lee, Hee-Yoon, Seog-Beom Song, Taek Kang, Yoon Jung Kim, and Su Jeong Geum. "Aziridinyl imines in organic synthesis: Development of tandem reaction strategies and application to total synthesis of natural products." Pure and Applied Chemistry 85, no. 4 (March 13, 2013): 741–53. http://dx.doi.org/10.1351/pac-con-12-10-01.

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Aziridinyl imines are well-known carbene equivalents because they are precursors of diazo compounds from which reactive intermediates can be produced. These carbene equivalents can be utilized as zwitterionic species, diradicals, or 4π system for cycloaddition reactions. Thus, the intermediates derived from aziridinyl imines have been used in the sulfur-ylide-mediated epoxide formation, tandem free-radical reactions, or cyclopropanation reaction via carbene intermediates to form trimethylenemethane (TMM) diyls, which undergo [2 + 3] cycloaddition reactions to form cyclopentanoids. Diazo compounds generated from aziridinyl imines also react with allenes to form TMM diyls. This reaction was utilized in tandem cycloaddition reactions of linear substrates to form polyquinanes. These tandem reaction strategies were successfully applied to the total synthesis of various cyclopentanoid natural products.

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Zhao, Peng, Simeng Wu, Chaoqi Ke, Xiaohua Liu, and Xiaoming Feng. "Chiral Lewis acid-catalyzed enantioselective cyclopropanation and C–H insertion reactions of vinyl ketones with α-diazoesters." Chemical Communications 54, no. 70 (2018): 9837–40. http://dx.doi.org/10.1039/c8cc05420g.

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39

Charette, André B., Carmela Molinaro, and Christian Brochu. "Catalytic Asymmetric Cyclopropanation of Allylic Alcohols with Titanium-TADDOLate: Scope of the Cyclopropanation Reaction." Journal of the American Chemical Society 123, no. 49 (December 2001): 12168–75. http://dx.doi.org/10.1021/ja0108382.

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Siddiqui, Saher H., Chandrasekhar Navuluri, and André B. Charette. "Enantioselective Synthesis of cis- and trans-Borocyclopropylmethanol: Simple Building Blocks To Access Heterocycle-Substituted Cyclopropylmethanols." Synthesis 51, no. 20 (August 1, 2019): 3834–46. http://dx.doi.org/10.1055/s-0037-1611896.

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An enantioselective and non-oxidative methodology was developed to obtain enantioenriched cyclopropyl boronates using a diethanolamine-promoted selective decomplexation of dioxaborolane. The non-oxidative decomplexation of the dioxaborolane ligand from the cyclopropylmethoxide species formed in the dioxaborolane-mediated Simmons–Smith cyclopropanation reaction provided the enantioenriched CIDA-based (CIDA = N-cyclohexyliminodiacetic acid) borocyclopropane in 92% yield and 95.6:4.4 er. A robustness screen has shown diethanolamine to be compatible with esters, carbamates and N-heterocycles, providing a tool to access enantioenriched cyclopropanes carrying not only base-sensitive but oxidizable functional groups as well. Diethanolamine was found to be compatible with the modified zinco-cyclopropanation reaction of allyl alcohol to remove residual dioxaborolane from the corresponding cis-N-heterocycle cyclopropylmethanol, thereby leading to improved yields.

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41

Kumar, Pradeep, Abhishek Dubey, and Anand Harbindu. "Enantio- and diastereocontrolled conversion of chiral epoxides to trans-cyclopropane carboxylates: application to the synthesis of cascarillic acid, grenadamide and l-(−)-CCG-II." Organic & Biomolecular Chemistry 10, no. 34 (2012): 6987–94. http://dx.doi.org/10.1039/c2ob25622c.

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A very concise and practical synthesis of cascarillic acid, grenadamide and l-CCG-II, a cyclopropane containing natural products is accomplished employing Wadsworth-Emmons cyclopropanation reaction as key step.

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Delion, Laëtitia, Thomas Poisson, Philippe Jubault, Xavier Pannecoucke, and André B. Charette. "Synthesis of fluorocyclopropanes via the enantioselective cyclopropanation of fluoro-substituted allylic alcohols using zinc carbenoids." Canadian Journal of Chemistry 98, no. 9 (September 2020): 516–23. http://dx.doi.org/10.1139/cjc-2020-0036.

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Cyclopropanation reactions using zinc carbenoids are a powerful means to access cyclopropanes. Described herein is an enantioselective version of the reaction using zinc reagents and a chiral dioxaborolane ligand in the generation of fluorocyclopropanes. Readily available 2- and 3-fluoroallylic alcohols were efficiently cyclopropanated in high yields and excellent enantioselectivities. This method provides access to a variety of structurally diverse chiral fluorocyclopropanes that can be used as useful chiral building blocks.

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Rachwalski, Michał, Aleksandra Buchcic-Szychowska, and Stanisław Leśniak. "Recent Advances in Selected Asymmetric Reactions Promoted by Chiral Catalysts: Cyclopropanations, Friedel–Crafts, Mannich, Michael and Other Zinc-Mediated Processes—An Update." Symmetry 13, no. 10 (September 22, 2021): 1762. http://dx.doi.org/10.3390/sym13101762.

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The main purpose of this review article is to present selected asymmetric synthesis reactions in which chemical and stereochemical outcomes are dependent on the use of an appropriate chiral catalyst. Optically pure or enantiomerically enriched products of such transformations may find further applications in various fields. Among an extremely wide variety of asymmetric reactions catalyzed by chiral systems, we are interested in: asymmetric cyclopropanation, Friedel–Crafts reaction, Mannich and Michael reaction, and other stereoselective processes conducted in the presence of zinc ions. This paper describes the achievements of the above-mentioned asymmetric transformations in the last three years. The choice of reactions is related to the research that has been carried out in our laboratory for many years.

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Bernardi, Fernando, Andrea Bottoni, and Gian Pietro Miscione. "DFT Study of the Palladium-Catalyzed Cyclopropanation Reaction." Organometallics 20, no. 13 (June 2001): 2751–58. http://dx.doi.org/10.1021/om0009280.

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Arai, Shigeru, Keiji Nakayama, Toshimasa Ishida, and Takayuki Shioiri. "Asymmetric cyclopropanation reaction Under phase-transfer catalyzed conditions." Tetrahedron Letters 40, no. 22 (May 1999): 4215–18. http://dx.doi.org/10.1016/s0040-4039(99)00679-6.

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Chen, Yao-Zhong, Teng Liu, Jie Zhu, Hui Zhang, and Lei Wu. "Transition-metal-free radical cleavage of a hydrazonyl N–S bond: tosyl radical-initiated cascade C(sp3)–OAr cleavage, sulfonyl rearrangement and atropisomeric cyclopropanation." Organic Chemistry Frontiers 5, no. 24 (2018): 3567–73. http://dx.doi.org/10.1039/c8qo00873f.

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Combination of 1,10-phenanthroline and potassium carbonate enables a radical cleavage of a hydrazonyl N–S bond, allowing a coupling reaction of N-tosylhydrazone and phosphinyl allene via cascade C–O cleavage, sulfonyl rearrangement and atropisomeric cyclopropanation.

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Luo, Si-Qin, Wei Liu, Ban-Feng Ruan, Shi-Lu Fan, Hui-Xia Zhu, Wei Tao, and Hua Xiao. "P(NMe2)3 mediated cyclopropanation of α-methylene-β-lactams for rapid syntheses of spirocyclopropyl β-lactams." Organic & Biomolecular Chemistry 18, no. 24 (2020): 4599–603. http://dx.doi.org/10.1039/d0ob00826e.

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A P(NMe₂)₃-promoted cyclopropanation of a C3-substituted α-methylene-β-lactam provides a rapid and user-friendly method to obtain pharmaceutically intriguing spirocyclopropyl β-lactams under mild reaction conditions.

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Singh, Meenakshi, V. Ravichandiran, Yogesh P. Bharitkar, and Abhijit Hazra. "Natural Products Containing Olefinic Bond: Important Substrates for Semi-synthetic Modification Towards Value Addition." Current Organic Chemistry 24, no. 7 (June 3, 2020): 709–45. http://dx.doi.org/10.2174/1385272824666200312125734.

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: Semi-synthesis, the way of preparing novel bioactive molecules via modification of compounds isolated from natural sources is very much useful nowadays in the drug discovery process. The modification is based on the reaction of functional group(s) present in a natural compound. Among the examples of functional group transformation, double bond modification is also common in the literature. Several reactions like hydrogenation, cyclopropanation, epoxidation, addition reaction (halogenations, hydroxylation), Michael addition, Heck reaction, cycloaddition, dipolar cycloaddition, etc. are employed for this purpose. In this review, we have tried to gather the reactions performed with several double bond containing classes of natural products like diterpenes, xanthones, sesquiterpene exomethylene lactones, diaryl heptanoids, steroidal lactones, triterpenoids, limonoids, and alkamides. Where available, the effects of transformations on the biological activities of the molecules are also mentioned.

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Zhou, Mingwei, Ke En, Yimin Hu, Yufang Xu, Hong C. Shen, and Xuhong Qian. "Zinc triflate-mediated cyclopropanation of oxindoles with vinyl diphenyl sulfonium triflate: a mild reaction with broad functional group compatibility." RSC Advances 7, no. 7 (2017): 3741–45. http://dx.doi.org/10.1039/c6ra24985j.

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Cambie, RC, SM Dudding, KC Higgs, SE Holroyd, PS Rutledge, and PD Woodgate. "Experiments Directed Towards the Synthesis of Anthracyclinones. XXII. Novel Cyclopropanation Reactions." Australian Journal of Chemistry 47, no. 8 (1994): 1561. http://dx.doi.org/10.1071/ch9941561.

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Iodine/potassium carbonate induced cyclization of hydroxyanthraquinones with ortho-allyl side chains gives iodomethyldihydrofuran anthraquinones which undergo a novel cyclopropanation reaction on treatment with methanolic potassium hydroxide, e.g. (9) gives (12) in 77% yield, and (10) gives (13) in 62% yield. The scope of the reaction is explored and a number of by-products are identified and, where possible, their formation is rationalized.

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