Academic literature on the topic '3-substituted cyclopropanes'
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Journal articles on the topic "3-substituted cyclopropanes"
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Schrumpf, G., and P. G. Jones. "Substituted cyclopropanes. 3. Hexachlorocyclopropane (redetermination)." Acta Crystallographica Section C Crystal Structure Communications 43, no. 6 (June 15, 1987): 1185–87. http://dx.doi.org/10.1107/s0108270187092576.
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Mlostoń, Grzegorz, Mateusz Kowalczyk, André U. Augustin, Peter G. Jones, and Daniel B. Werz. "Ferrocenyl-substituted tetrahydrothiophenes via formal [3 + 2]-cycloaddition reactions of ferrocenyl thioketones with donor–acceptor cyclopropanes." Beilstein Journal of Organic Chemistry 16 (June 10, 2020): 1288–95. http://dx.doi.org/10.3762/bjoc.16.109.
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Ferrocenyl thioketones reacted with donor–acceptor cyclopropanes in dichloromethane at room temperature in the presence of catalytic amounts of Sc(OTf)3 yielding tetrahydrothiophene derivatives, products of formal [3 + 2]-cycloaddition reactions, in moderate to high yields. In all studied cases, dimethyl 2-arylcyclopropane dicarboxylates reacted with the corresponding aryl ferrocenyl thioketones in a completely diastereoselective manner to form single products in which (C-2)-Ar and (C-5)-ferrocenyl groups were oriented in a cis-fashion. In contrast, the same cyclopropanes underwent reaction with alkyl ferrocenyl thioketones to form nearly equal amounts of both diastereoisomeric tetrahydrothiophenes. A low selectivity was also observed in the reaction of a 2-phthalimide-derived cyclopropane with ferrocenyl phenyl thioketone.
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Ledingham, Edward, Christopher Merritt, Christopher Sumby, Michelle Taylor, and Ben Greatrex. "Stereoselective Cyclopropanation of (–)-Levoglucosenone Derivatives Using Sulfonium and Sulfoxonium Ylides." Synthesis 49, no. 12 (March 17, 2017): 2652–62. http://dx.doi.org/10.1055/s-0036-1588971.
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The synthesis of tri- and tetrasubstituted cyclopropanes from 3-aryl-substituted levoglucosenones (LGO) has been developed. In contrast to the unstabilised ylide dimethylsulfonium methylide which gives epoxides from LGO via 1,2-addition, we have found that the soft nucleophile dimethylsulfoxonium methylide affords cyclopropanes in moderate yields from LGO and in excellent yields and stereoselectivity with 3-aryl LGO derivatives. The use of 1,1,3,3-tetramethylguanidine as base in DMSO to generate the ylide provided the best yields and shortest reaction times. Ester stabilised sulfonium ylides could also be used to generate tetrasubstituted cyclopropane derivatives. One of the products was converted into a cyclopropyl lactone via Baeyer–Villiger oxidation to demonstrate the utility of applying cyclopropanation chemistry to LGO.
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Vereshchagin, Anatolii N., Michail N. Elinson, Nikita O. Stepanov, and Gennady I. Nikishin. "New Way to Substitute Tetracyanocyclopropanes: One-Pot Cascade Assembling of Carbonyls and Malononitrile by the Only Bromine Direct Action." ISRN Organic Chemistry 2011 (July 26, 2011): 1–5. http://dx.doi.org/10.5402/2011/469453.
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The new type of the chemical cascade reaction was found: formation of cyclopropanes from carbonyl compounds and CH acid by the only bromine direct action. The action of aqueous bromine on the carbonyl compounds and malononitrile in EtOH-H2O solutions in the presence of NaOAc results in the formation of 3-substituted 1,1,2,2-tetracyanocyclopropanes in 48–93% yields. The latter are well-known precursors for the different bicyclic heterosystems, among them those containing cyclopropane ring and those possessing different types of pharmacological activity.
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Xie, Ming-Sheng, Yong Wang, Jian-Ping Li, Cong Du, Yan-Yan Zhang, Er-Jun Hao, Yi-Ming Zhang, Gui-Rong Qu, and Hai-Ming Guo. "A straightforward entry to chiral carbocyclic nucleoside analogues via the enantioselective [3+2] cycloaddition of α-nucleobase substituted acrylates." Chemical Communications 51, no. 62 (2015): 12451–54. http://dx.doi.org/10.1039/c5cc04832j.
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Su, Zhenjie, Siran Qian, Shuwen Xue, and Cunde Wang. "DBU-mediated [4 + 1] annulations of donor–acceptor cyclopropanes with carbon disulfide or thiourea for synthesis of 2-aminothiophene-3-carboxylates." Organic & Biomolecular Chemistry 15, no. 37 (2017): 7878–86. http://dx.doi.org/10.1039/c7ob01886j.
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Chung, Eun Hee, Jungra Shim, and Woo Ki Chae. "Photochemical cis–trans isomerization of 1,2-dibenzoyl-3-substituted cyclopropanes." Journal of Photochemistry and Photobiology A: Chemistry 129, no. 1-2 (December 1999): 43–48. http://dx.doi.org/10.1016/s1010-6030(99)00195-1.
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Padmaja, Adivireddi, Kalluru Ramachandra Reddy, Venkatapuram Padmavathi, and Dandu Bhaskar Reddy. "Cyclopropanation of Phenyl Styryl Sulfones with Phenacylsulfonium Ylides Under Phase-Transfer Catalysis." Collection of Czechoslovak Chemical Communications 63, no. 6 (1998): 835–41. http://dx.doi.org/10.1135/cccc19980835.
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Cyclopropanation of substituted phenyl styryl sulfones 1 with dimethylsulfonium phenacylides was carried out by two different methods (under PTC catalysis with in situ generation of the ylides and by direct addition of ylides) to obtain a series of substituted 1-benzenesulfonyl-2-benzoyl-3-phenylcyclopropanes 2. The PTC method was found to be more facile and efficient. The spectral data of cyclopropanes 2 are discussed.
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Wu, Wen‐Feng, Jin‐Hong Lin, Ji‐Chang Xiao, Yu‐Cai Cao, and Yanfang Ma. "Recent Advances in the Synthesis of CF 3 ‐ or HCF 2 ‐Substituted Cyclopropanes." Asian Journal of Organic Chemistry 10, no. 3 (February 16, 2021): 485–95. http://dx.doi.org/10.1002/ajoc.202000723.
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Ortega, Alesandere, Uxue Uria, Tomás Tejero, Liher Prieto, Efraim Reyes, Pedro Merino, and Jose L. Vicario. "Brønsted Acid Catalyzed (4 + 2) Cyclocondensation of 3-Substituted Indoles with Donor–Acceptor Cyclopropanes." Organic Letters 23, no. 6 (March 9, 2021): 2326–31. http://dx.doi.org/10.1021/acs.orglett.1c00470.
Full textDissertations / Theses on the topic "3-substituted cyclopropanes"
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Goudreau, Sébastien R. "Les esters cyclopropane-1,1-dicarboxyliques et les dérivés cyclopropaniques 1,2,3-substitués : synthèses et applications." Thèse, 2010. http://hdl.handle.net/1866/4322.
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Les cyclopropanes sont des motifs d’une grande importance puisqu’ils sont présents dans plusieurs molécules biologiquement actives en plus d’être de puissants intermédiaires dans la synthèse de molécules complexes. Au cours de cet ouvrage, nous avons développé une nouvelle méthode générale pour la synthèse d’ylures d’iodonium de malonates, soit d’importants précurseurs d’esters cyclopropane-1,1-dicarboxyliques. Ainsi, à l’aide de ces ylures, une méthode très efficace pour la synthèse d’esters cyclopropane-1,1-dicarboxyliques racémiques a été développée. Des travaux ont aussi été entrepris pour la synthèse énantiosélective de ces composés. Par ailleurs, les esters cyclopropane-1,1-dicarboxyliques ont été utilisés dans le développement de deux nouvelles méthodologies, soit dans une réaction de cycloaddition (3+3) avec des imines d’azométhines et dans la formation d’allènes par l’addition-1,7 de cuprates.
Nous avons aussi poursuivi l’étude synthétique du cylindrocyclophane F impliquant l’utilisation de cyclopropanes pour le contrôle des centres chiraux. Ainsi l’addition-1,5 d’un cuprate sur un ester cyclopropane-1,1-dicarboxylique a été utilisée comme l’une des étapes clés de notre synthèse. L’autre centre chiral a pu être contrôlé par l’hydrogénolyse sélective d’un cyclopropylméthanol. Ces études ont, par ailleurs, mené au développement d’une nouvelle réaction d’arylcyclopropanation énantiosélective utilisant des carbénoïdes de zinc générés in situ à partir de réactifs diazoïques. Cette méthode permet d’accéder très efficacement aux cyclopropanes 1,2,3-substitués. De plus, nous avons développé la première réaction de Simmons-Smith catalytique en zinc menant à un produit énantioenrichi.Cyclopropanes are important scaffolds as they are present in many biologically actives compounds and they are useful intermediates in the synthesis of complex molecules. In this thesis, we developed a novel general method for the synthesis of iodonium ylides of malonates, which are important precursors in the synthesis of cyclopropane-1,1-dicarboxylic esters. From these ylides, a method to generate racemic cyclopropane-1,1-dicarboxylic esters very efficiently was developed. Further works was also achieved on an asymmetric version of this reaction. Cyclopropane-1,1-dicarboxylic esters were used to develop two new methods: a (3+3) cycloaddition reaction with azomethine imines and the formation of allenes by the 1,7-addition of cuprates. We also continued our studies towards the total synthesis of cylindrocyclophane F, which use the cyclopropanes to control all chiral centers. The 1,5-addition of a cuprate on a cyclopropane-1,1-dicarboxylic ester was utilized as one of the key steps of our synthesis. The other chiral centre was controlled by the hydrogenolysis of a cyclopropylmethanol. Moreover, these studies led to the development of a novel highly enantioselective arylcyclopropanation reaction using zinc carbenoids generated in situ from diazo compounds. This method allows the efficient access to 1,2,3-substituted cyclopropanes. Moreover, we developed the first Simmons-Smith reaction using a catalytic amount of zinc to produce an enantioenriched product.
Book chapters on the topic "3-substituted cyclopropanes"
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Reißig, H. U. "Donor-Acceptor-Substituted Cyclopropanes via Fischer Carbene Complexes." In Organometallics in Organic Synthesis 2, 311–22. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74269-9_17.
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Taber, Douglass. "Stereocontrolled Carbocyclic Construction: (-)-Mintlactone (Bates), (-)-Gleenol (Kobayashi), (-)-Vibralactone C (Snider)." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0081.
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Nigel S. Simpkins, now at the University of Birmingham, found (Chem. Commun. 2008, 5390) that the prochiral cyclopropane amide 1 could be deprotonated to give, after alkylation, the substituted cyclopropane 3 with high enanantio- and diastereocontrol. In the course of a synthesis of (+)-Lineatin, Ramon Alibés of the Universitat Autònoma de Barcelona optimized (J. Org. Chem. 2008, 73, 5944) the photochemical cycloaddition of 4 and 5 to give, after reductive dechlorination, the cyclobutene 6. In a related reaction, José L. García Ruano and M. Rosario Martín of the Universidad Autónoma de Madrid observed (J. Org. Chem. 2008, 73, 9366) that the cycloaddition of 8 to 7 proceeded with high regio- and diastereocontrol, to give the cyclopentene 9. Joseph M. Ready of UT Southwestern in Dallas developed (Angew. Chem. Int. Ed. 2008, 47, 7068) a powerful new cyclopentannulation, condensing the cyclopropane derived from the addition of 11 to 10 with the protected ynolate 12 to give 13, in the presence of a modified Lewis acid catalyst. Chun-Chen Liao of the National Tsing Hua University, Hsinchu described (Angew. Chem. Int. Ed. 2008, 47, 7325) the oxidative ring contraction of the o-alkoxy phenol 14 to the cyclopentenone 15. Stéphane Quideau of the Université de Bordeaux reported (Organic Lett. 2008, 10, 5211) a related ring contraction. We uncovered (J. Org. Chem. 2008, 73, 9479) a simple protocol for the in situ conversion of an ω-alkenyl ketone such as 16 to the corresponding diazo compound, leading, via dipolar cycloaddition, to the adduct 17. Ulrich Zutter of Roche Basel described (J. Org. Chem. 2008 , 73, 4895), in a synthesis of Tamiflu, the hydrogenation of 19 to give the cyclohexane with all-cis diastereocontrol. Selective removal of the methyl ethers with trimethylsilyl iodide set the stage for enzymatic ester hydrolysis, delivering 20 in high ee.
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Taber, Douglass F. "Other Methods for Carbocyclic Construction: The Porco Synthesis of (-)-Hyperibone K." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0081.
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Varinder K. Aggarwal of the University of Bristol described (Angew. Chem. Int. Ed. 2010, 49, 6673) the conversion of the Sharpless-derived epoxide 1 into the cyclopropane 2. Christopher D. Bray of Queen Mary University of London established (Chem. Commun. 2010, 46, 5867) that the related conversion of 3 to 5 proceeded with high diastereocontrol. Javier Read de Alaniz of the University of California, Santa Barbara, extended (Angew. Chem. Int. Ed. 2010, 49, 9484) the Piancatelli rearrangement of a furyl carbinol 6 to allow inclusion of an amine 7, to give 8. Issa Yavari of Tarbiat Modares University described (Synlett 2010, 2293) the dimerization of 9 with an amine to give 10. Jeremy E. Wulff of the University of Victoria condensed (J. Org. Chem. 2010, 75, 6312) the dienone 11 with the commercial butadiene sulfone 12 to give the highly substituted cyclopentane 13. Robert M. Williams of Colorado State University showed (Tetrahedron Lett. 2010, 51, 6557) that the condensation of 14 with formaldehyde delivered the cyclopentanone 15 with high diastereocontrol. D. Srinivasa Reddy of Advinus Therapeutics devised (Tetrahedron Lett. 2010, 51, 5291) conditions for the tandem conjugate addition/intramolecular alkylation conversion of 16 to 17. Marie E. Krafft of Florida State University reported (Synlett 2010, 2583) a related intramolecular alkylation protocol. Takao Ikariya of the Tokyo Institute of Technology effected (J. Am. Chem. Soc. 2010, 132, 11414) the enantioselective Ru-mediated hydrogenation of bicyclic imides such as 18. This transformation worked equally well for three-, four-, five-, six-, and seven-membered rings. Stefan France of the Georgia Institute of Technology developed (Org. Lett. 2010, 12, 5684) a catalytic protocol for the homo-Nazarov rearrangement of the doubly activated cyclopropane 20 to the cyclohexanone 21. Richard P. Hsung of the University of Wisconsin effected (Org. Lett. 2010, 12, 5768) the highly diastereoselective rearrangement of the triene 22 to the cyclohexadiene 23. Strategies for polycyclic construction are also important. Sylvain Canesi of the Université de Québec devised (Org. Lett. 2010, 12, 4368) the oxidative cyclization of 24 to 25.
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Taber, Douglass F. "Carbocyclic Ring Construction: The Nicolaou Synthesis of Myceliothermophin E." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0082.
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Nan Zheng of the University of Arkansas developed (Adv. Synth. Catal. 2014, 356, 2831) a Ru catalyst for the addition of an amino cyclopropane 1 to an alkyne 2 to give 3. The reaction proceeded with high regiocontrol, but only modest stereocontrol. Alain De Mesmaeker of Syngenta Crop Protection, Switzerland found (Tetrahedron Lett. 2014, 55, 6577) that the β,γ-unsaturated amide 4 worked particularly well as a precursor to the keteniminium that cyclized to give, after hydrolysis, the cyclobutanone 5. Baeyer–Villiger oxidation of 5 led to 5-deoxystrigol 6. David Tymann and Martin Hiersemann of the Technische Universität Dortmund have been exploring (Org. Lett. 2014, 16, 4062; Synthesis 2014, 46, 3110) the intramolecular carbonyl ene reaction as a tool for the assembly of highly substituted cyclopentanes, as in the conversion of 7 to 8. On oxidation, 8 was readily carried on to the alkene 9. James L. Leighton of Columbia University conceived (J. Am. Chem. Soc. 2014, 136, 9878) the cascade transformation of 10 to 12. Deprotonation/silylation set the stage for Claisen rearrangement to give 11. The subsequent Cope rearrangement is an equilibrium process, driven by the ring strain of 11. K. C. Nicolaou of Rice University described (Angew. Chem. Int. Ed. 2014, 53, 10970) the total synthesis of the cytotoxic tetramic acid derivative myceliothermophin E 15. A key step in the synthesis was the intramolecular Michael addition/ aldol condensation that converted 13 to 14.
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Taber, Douglass F. "Metal-Mediated Ring Construction: The Hoveyda Synthesis of (–)-Nakadomarin A." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0077.
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John F. Hartwig of the University of California, Berkeley effected (J. Am. Chem. Soc. 2013, 135, 3375) selective borylation of the cyclopropane 1 to give 2. It would be particularly useful if this borylation could be made enantioselective. Eric M. Ferreira of Colorado State University showed (Org. Lett. 2013, 15, 1772) that the enantomeric excess of 3 was transferred to the highly substituted cyclopropane 4. Antonio M. Echavarren of ICIQ Tarragona demonstrated (Org. Lett. 2013, 15, 1576) that Au-mediated cyclobutene construction could be used to form the medium ring of 6. Joseph M. Fox of the University of Delaware developed (J. Am. Chem. Soc. 2013, 135, 9283) what promises to be a general enantioselective route to cyclobutanes such as 8 by way of the intermediate bicyclobutane (not illustrated). Huw M.L. Davies of Emory University reported (Org. Lett. 2013, 15, 310) a preliminary investigation in this same direction. Masahisa Nakada of Waseda University prepared (Org. Lett. 2013, 15, 1004) the cyclopentane 10 by enantioselective cyclization of 9 followed by reductive opening. Young-Ger Suh of Seoul National University cyclized (Org. Lett. 2013, 15, 531) the lactone 11 to the cyclopentane 12. Xavier Ariza and Jaume Farràs of the Universitat de Barcelona optimized (J. Org. Chem. 2013, 78, 5482) the Ti-mediated reductive cyclization of 13 to 14. The hydrogenation catalyst reduced the intermediate Ti–C bond without affecting the alkene. Erick M. Carreira of ETH Zürich observed (Angew. Chem. Int. Ed. 2013, 52, 5382) that a sterically demanding Rh catalyst mediated the highly diastereoselective cyclization of 15 to 16. The ketone 16 was the key intermediate in a synthesis of the epoxyisoprostanes. Jianrong (Steve) Zhou of Nanyang Technological University used (Angew. Chem. Int. Ed. 2013, 52, 4906) a Pd catalyst to effect the coupling of 17 with the prochiral 18. Geum-Sook Hwang and Do Hyun Ryu of Sungkyunkwan University devised (J. Am. Chem. Soc. 2013, 135, 7126) a boron catalyst to effect the addition of the diazo ester 21 to 20. They showed that the sidechain stereocenter was effective in directing the subsequent hydrogenation of 22.
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Taber, Douglass F. "New Methods for Carbocyclic Construction: The Kim Synthesis of Pentalenene." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0080.
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Daesung Lee of the University of Illinois, Chicago, taking advantage of the facile insertion of an alkylidene carbene into a C-Si bond, established (J. Am. Chem. Soc. 2010, 132, 6640) a general method for the conversion of an α-silyl ketone 1 into the silyl cyclopropene 3. Christopher D. Bray of Queen Mary University showed (J. Org. Chem. 2010, 75, 4652) that the sulfonyl phosphonate 5 converted the enantiomerically pure epoxide 4 into the cyclopropane 6. Paul Margaretha of the University of Hamburg observed (Organic Lett. 2010, 12, 728) smooth photochemical combination of 7 and 8 to give 9 with high diastereocontrol. Tõnis Kanger of the Tallinn University of Technology devised (Organic Lett. 2010, 12, 2230) the three-component coupling of 10, 11, and diethyl amine to give, after reduction, the highly substituted cyclobutane 12. Min Shi of the Shanghai Institute of Organic Chemistry uncovered (J. Org. Chem. 2010, 75, 902) an interesting new thermal rearrangement: the conversion of 13 to 14. José G. Ávila-Zárraga of the Universidad Nacional Autónoma de México applied (Tetrahedron Lett. 2010, 51, 2232) Pd catalysis to the cyclization of the epoxy nitrile 15, redirecting the reaction from the expected cyclobutane to the cyclopentanol 16. Ullrich Jahn of the Academy of Sciences of the Czech Republic effected (J. Org. Chem. 2010, 75, 4480) the oxidative radical cyclization of 17 to 18. Initial deprotonation of the substrate with t -BuMgCl switched the product to the trans diastereomer. Jonathan W. Burton of the University of Oxford employed (Organic Lett. 2010, 12, 2738) a related oxidative cyclization for the diastereoselective conversion of 19 to 20. E. J. Corey of Harvard University reported (Organic Lett. 2010, 12, 300) a new ligand for the enantioselective Ni-mediated reduction of 21 to 22. Shu-Li You, also of the Shanghai Institute of Organic Chemistry, established (J. Am. Chem. Soc. 2010, 132, 4056) that the alcohol 23, readily prepared by oxidation of p -cresol, could be cyclized to the crystalline 25 in high ee.
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Lambert, Tristan H. "Advances in Heterocyclic Aromatic Construction." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0068.
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Rubén Vicente and Luis A. López at the University of Oviedo in Spain reported (Angew. Chem. Int. Ed. 2012, 51, 8063) the synthesis of cyclopropyl furan 2 from alkylidene 1 and styrene by way of a zinc carbene intermediate. The same substrate 1 was also converted (Angew. Chem. Int. Ed. 2012, 51, 12128) to furan 3 via catalysis with tetrahydrothiophene in the presence of benzoic acid by J. Stephen Clark at the University of Glasgow. Xue-Long Hou at the Shanghai Institute of Organic Chemistry discovered (Org. Lett. 2012, 14, 5756) that palladacycle 6 catalyzes the conversion of bicyclic alkene 4 and alkynone 5 to furan 7. A silver-mediated C–H/C–H functionalization strategy for the synthesis of furan 9 from alkyne 8 and ethyl acetoacetate was developed (J. Am. Chem. Soc. 2012, 134, 5766) by Aiwen Lei at Wuhan University. Ning Jiao at Peking University and East China Normal University found (Org. Lett. 2012, 14, 4926) that azide 10 and aldehyde 11 could be converted to either pyrrole 12 or 13 with complete regiocontrol by judicious choice of a metal catalyst. Meanwhile, Michael A. Kerr at the University of Western Ontario developed (Angew. Chem. Int. Ed. 2012, 51, 11088) a multicomponent synthesis of pyrrole 16 involving the merger of nitrone 14 and the donor–acceptor cyclopropane 15. The pyrrole 16 was subsequently converted to an intermediate in the synthesis of the cholesterol-lowering drug compound Lipitor. A robust synthesis of the ynone trifluoroboronate 17 was developed (Org. Lett. 2012, 14, 5354) by James D. Kirkham and Joseph P.A. Harrity at the University of Sheffield, which thus allowed for the ready production of trifluoroboronate-substituted pyrazole 18. An alternative pyrazole synthesis via oxidative closure of unsaturated hydrazine 19 to produce 20 was reported (Org. Lett. 2012, 14, 5030) by Yu Rao at Tsinghua University. A unique fluoropyrazole construction was developed (Angew. Chem. Int. Ed. 2012, 51, 12059) by Junji Ichikawa at the University of Tsukuba that involved nucleophilic substitution of two of the fluorides in 21 to form pyrazole 22.
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Taber, Douglass F. "Organocatalytic Carbocyclic Construction: The Christmann Synthesis of (+)-Rotundial." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0069.
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Karl Anker Jørgensen of Aarhus University found (Angew. Chem. Int. Ed. 2009, 48, 6650) that an organocatalyst could mediate the fragmentation of the prochiral cyclopropane 1 with high ee to the easily epimerized product 2. Guofu Zhong of Nanyang Technological University devised (Angew. Chem. Int. Ed. 2009, 48, 6089) a dipolar cycloaddition strategy for the organocatalyzed combination of 3 and 4 with PhNHOH to give the highly substituted cyclopentane 5. Professor Jørgensen also established (Angew. Chem. Int. Ed. 2009, 48, 7338) that conjugate addition of 7 to the prochiral cyclohexenone 6 proceeded with high ee. The initial adduct could be converted into the alkene 8, the alkyne, or the ketone. Wen-Jing Xiao of Central China Normal University, following up on the work of Gong and Cheng, developed (Tetrahedron 2009, 65, 9238) a simple organocatalyst for the desymmetrizing Michael addition of 9 to 10 to give 11 with high de and ee. Control of sidechain chirality is an important aspect of carbocyclic construction. Samuel H. Gellman of the University of Wisconsin demonstrated (J. Am. Chem. Soc. 2009, 131, 16018) that the organocatalyzed addition of 13 to 12 proceeded with high facial selectivity and excellent diastereocontrol. In a complementary approach, Alexander J. A. Cobb of the University of Reading optimized (J. Am. Chem. Soc. 2009, 131, 16016) an organocatalyst for the cyclization of 15 to 16, again with high facial selectivity and excellent diastereocontrol. Ying-Chun Chen of the West China School of Pharmacy established (Organic Lett. 2009, 11, 4660) conditions for the organocatalyzed combination of 17 with 18 to give 19. In a related approach, Bor-Cherng Hong of the National Chung Cheng University showed (Organic Lett. 2009, 11, 5246) that 20, 21, and 22 could be combined under organocatalysis to give 23 in high ee with excellent diastereocontrol. Both of these approaches, and several others that have been published recently, were carried out with aryl substituents. It remains to be seen whether alkyl substituents, which would be more useful in a target-directed synthesis, would be compatible with these methods for ring construction.
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Taber, Douglass F. "Organocatalytic Carbocyclic Construction: The You Synthesis of (–)-Mesembrine." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0070.
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Frank Glorius of the Universität Münster devised (Angew. Chem. Int. Ed. 2011, 50, 12626) a catalyst for the enantioselective acylation of a cyclopropene 1 to the ketone 3. Geum-Sook Hwang of Chungnam National University and Do Hyun Ryu of Sungkyunkwan University effected (J. Am. Chem. Soc. 2011, 133, 20708) the enantioselective addition of the diazo ester 5 to an α,β-unsaturated aldehyde 4 to give the cyclopropane 6. We showed (J. Org. Chem. 2011, 76, 7614) that face-selective allylation of an α-iodo enone 7 followed by Suzuki coupling and oxy-Cope rearrangement delivered the cyclopentanone 9. Karl Anker Jørgensen of Aarhus University combined (Org. Lett. 2011, 13, 4790) two organocatalysts to effect the addition of 11 to an α,β-unsaturated aldehyde 10, leading to the cyclopentenone 12. Tomislav Rovis of Colorado State University also used (Chem. Sci. 2011, 2, 1835) two organocatalysts to condense 13 with 14 to give the cyclopentanone 15. Gregory C. Fu, now at CalTech, found (J. Am. Chem. Soc. 2011, 133, 12293) that both enantiomers of the racemic allene 16 combined with 17 to give the cyclopentene 18 in high ee. Piotr Kwiatkowski of the University of Warsaw found (Org. Lett. 2011, 13, 3624) that under elevated pressure (8–10 kbar), enantioselective conjugate addition of nitromethane proceeded well even with a β-substituted cyclohexenone 19. Marco Bella of the Università di Roma observed (Adv. Synth. Catal. 2011, 353, 2648) remarkable diastereoselectivity in the addition of the aldehyde 22 to an activated acceptor 21. Following the procedure of List, Jiong Yang of Texas A&M University cyclized (Org. Lett. 2011, 13, 5696) 24 to 25 in high ee. Bor-Cherng Hong of the National Chung Cheng University described (Synthesis 2011, 1887) the double Michael combination of 26 with 27 to give 28 in high ee. Observing a secondary 13C isotope effect only at the β-carbon of 30, Li Deng of Brandeis University concluded (Chem. Sci. 2011, 2, 1940) that the addition to 29 was stepwise, not concerted. In contrast, the cyclization of 32 to 33 reported (Org. Lett. 2011, 13, 3932) by Tadeusz F. Molinski of the University of California San Diego likely was concerted.