Asymmetric Cyclopropanations by Rhodium(II) N-(Arylsulfonyl)prolinate Catalyzed Decomposition of Vinyldiazomethanes in the Presence of Alkenes. Practical Enantioselective Synthesis of the Four Stereoisomers of 2-Phenylcyclopropan-1-amino Acid

Autor:	Michael J. Fall, Huw M. L. Davies, Paul R. Bruzinski, and Norman Kong, Debra H. Lake
Rok vydání:	1996
Předmět:	Sulfonyl chemistry.chemical_classification Enantioselective synthesis chemistry.chemical_element General Chemistry Biochemistry Asymmetric induction Catalysis Rhodium Pentane Solvent chemistry.chemical_compound Colloid and Surface Chemistry chemistry Organic chemistry Carbenoid
Zdroj:	Journal of the American Chemical Society. 118:6897-6907
ISSN:	1520-5126 0002-7863
Popis:	The rhodium N-(arylsulfonyl)prolinate catalyzed decomposition of vinyldiazomethanes in the presence of alkenes leads to a very general method for the synthesis of functionalized cyclopropanes in a highly diastereoselective and enantioselective mode. A detailed study was undertaken to determine the key factors that control the enantioselectivity of this process. The highest levels of enantioselectivity were obtained using cyclic N-(arylsulfonyl)amino acids as ligands for the dirhodium catalyst, and the optimized catalyst was tetrakis[N-[(4-dodecylphenyl)sulfonyl]-(L)-prolinato]dirhodium. The carbenoid structure has a critical effect on the degree of asymmetric induction, and the combination of a small electron-withdrawing group such as a methyl ester and an electron-donating group such as vinyl or phenyl resulted in the highest levels of enantioselectivity. The use of electron neutral alkenes and pentane as solvent also enhanced the enantioselectivity of the process. The synthetic utility of this chemistry...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f2b1dafd7c9d888c989bba7f607f3f9a https://doi.org/10.1021/ja9604931 Zobrazit plný text záznamu