Academic literature on the topic 'Tandem conjugate addition-Dieckmann condensation'

Babak Borhan of Michigan State University found (Angew. Chem. Int. Ed. 2011, 50, 2593) that the ligand developed for asymmetric osmylation worked well for the enantioselective cyclization of 1 to 2. Kyungsoo Oh of IUPUI devised (Org. Lett. 2011, 13, 1306) a Co catalyst for the stereocontrolled addition of 4 to 3 to give 5. Michael J. Krische of the University of Texas Austin prepared (Angew. Chem. Int. Ed. 2011, 50, 3493) 8 by Ir*-mediated oxidation/addition of 7 to 6. Yixin Lu of the National University of Singapore employed (Angew. Chem. Int. Ed. 2011, 50, 1861) an organocatalyst to effect the stereocontrolled addition of 10 to 9. Naoya Kumagai and Masakatsu Shibasaki of the Institute of Microbial Chemistry, Tokyo took advantage (J. Am. Chem. Soc. 2011, 133, 5554) of the soft Lewis basicity of 13 to effect stereocontrolled condensation with 12. Yujiro Hayashi of the Tokyo University of Science found (Angew. Chem. Int. Ed. 2011, 50, 2804, not illustrated) that aqueous chloroacetaldehyde participated well in crossed aldol condensations. Andrew V. Malkov, now at Loughborough University, and Pavel Kocovsky of the University of Glasgow showed (J. Org. Chem. 2011, 76, 4800) that the inexpensive mixed crotyl silane 16 could be added to 15 with high stereocontrol. Shigeki Matsunaga of the University of Tokyo and Professor Shibasaki opened (J. Am. Chem. Soc. 2011, 133, 5791) the meso aziridine 18 with malonate 19 to give 20. Masahiro Terada of Tohoku University effected (Org. Lett. 2011, 13, 2026) the conjugate addition of 22 to 21 with high stereocontrol. Jinxing Ye of the East China University of Science and Technology reported (Angew. Chem. Int. Ed. 2011, 50, 3232, not illustrated) a related conjugate addition. Kian L. Tian of Boston College observed (Org. Lett. 2011, 13, 2686) that the kinetic hydroformylation of 24 set the relative configuration of two stereogenic centers. Alexandre Alexakis and Clément Mazet of the Université de Genève established (Angew. Chem. Int. Ed. 2011, 50, 2354) a tandem one-pot procedure for the addition of 26 to 27 to give 28.

Josep Bonjoch of the Universitat de Barcelona extended (Org. Lett. 2013, 15, 326) the Jørgensen variation of the Robinson annulation to the amine-substituted β-keto ester 1. The product cis-fused sulfonamide 3, readily brought to high ee by recrystallization, was carried onto (+)-lycoposerramine Z 4. Intramolecular ketene 2+2 cycloaddition is underdeveloped as a synthetic method. Kozo Shishido of the University of Tokushima observed (Org. Lett. 2013, 15, 200) high diastereoselectivity in the cyclization of 5 to 6. This set the stage for the synthesis of (-)-esermethole 7. Jieping Zhu of the Ecole Polytechnique Fédérale de Lausanne prepared (Angew. Chem. Int. Ed. 2013, 52, 3272) the cyclopentene 8 by coupling the alkenyl triflate with the salt of an α-alkyl arylacetic acid. Ozonolysis followed by reductive work-up led to a diamino keto aldehyde that cyclized to 9. Benzyl ether cleavage delivered (±)-goniomitine 10. Richard J.K. Taylor of the University of York developed (Angew. Chem. Int. Ed. 2013, 52, 1490) a powerful tandem conjugate addition-imination-methanolysis protocol. He had already prepared (+)-grandisine 11 from N-Boc prolinol. Amination-imination converted 11 to (+)-grandisine 12. This was opened by methanolysis to (+)-grandisine G 13. Four diastereomers are possible from the condensation of 14 and 15. Eric N. Jacobsen of Harvard University developed (Org. Lett. 2013, 15, 706) an organocatalyst that delivered 16 as the dominant diastereomer. This was readily converted to (+)-reserpine, the enantiomer of the natural product.

Hisashi Yamamoto of the University of Chicago devised (J. Am. Chem. Soc. 2010, 132, 7878) catalyst systems for the enantioselective epoxidation of a Z -homoallylic alcohol 1. Michael J. Krische of the University of Texas developed (J. Am. Chem. Soc. 2010, 132, 1760) a catalyst system for the highly stereoselective addition of the vinyl acetal 5 to an aldehyde 4. Joëlle Prunet of the University of Glasgow showed (Tetrahedron Lett. 2010, 51, 256) that the tandem cyclization/Julia olefination from 7 also proceeded with high stereocontrol. Professor Yamamoto established (J. Am. Chem. Soc. 2010, 132, 5354) that depending on conditions, the aldol condensation of 10 could be directed selectively toward either diastereomer of the product 12. James M. Takacs of the University of Nebraska effected (J. Am. Chem. Soc. 2010, 132, 1740) the enantioselective hydroboration of 10. The other geometric isomer of 10 gave the alternative diastereomer of 12, also with high ee. John Limanto and Shane W. Krska of Merck Process optimized (Organic Lett . 2010, 12, 512) the dynamic kinetic reduction of 13 , giving 14 with excellent diastereocontrol. Professor Krische extended (J. Am. Chem. Soc. 2010, 132, 4562) his reductive homologation to the (racemic) carbonate 15, delivering 16 with excellent dr and ee. Hirokazu Urabe of the Tokyo Institute of Technology showed (Organic Lett. 2010, 12, 1012) that a Grignard reagent under iron catalysis opened the epoxide 17, readily available by Jørgensen-Cordova epoxidation followed by homologation, with clean inversion and high regiocontrol. Fraser F. Fleming of Duquesne University developed (Organic Lett. 2010, 12, 3030) a general route to quaternary alkylated centers by alkylation of nitriles such as 19. Shigeki Matsunaga and Masakatsu Shibasaki of the University of Tokyo devised (J. Am. Chem. Soc. 2010, 132, 3666) a Ni catalyst for the stereoselective conjugate addition of the lactam 22 to a nitroalkene 21. Aldehydes can also be added to nitroalkenes with high dr and ee, as illustrated by the conversion of 24 to 26 reported (J. Am. Chem. Soc. 2010, 132, 50) by Bukuo Ni of Texas A&M University, Commerce.

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.