Gleason-type chiralauxiliaries were used for the synthesis of a novel class of sulfonium salts, obtained via methylation of the sulfide with Meerwein's salt. The salts were reacted with aldehydes under basic conditions to provide epoxy amides, which were reduced to their corresponding epoxy alcohols in excellent enantiomeric excesses. Interestingly, it was feasible to synthesize both enantiomeric
A new type of chiral sulfur ylides has been synthesized and their reactivities against carbonyl compounds tested, showing a high degree of stereoselectivity in the formation of transepoxyamides under very mild reaction conditions.
A new type of chiral sulfoniumsalts that are characterized by a bicyclic system has been designed and synthesized from α‐amino acids. Their corresponding ylides, which were prepared by basic treatment of the sulfoniumsalts, reacted smoothly with a broad array of simple and chiral aldehydes to provide trans‐epoxy amides in reasonable to very good yields and excellent stereoselectivities (>98 %). The
Study on the stereochemical control of dihydroxylation of vinyl epoxides and their derivatives
作者:Giuliana Righi、Emanuela Mandic’、Gaia Clara Mercedes Naponiello、Paolo Bovicelli、Ilaria Tirotta
DOI:10.1016/j.tet.2012.02.029
日期:2012.4
The results obtained from a study on the stereochemical control in the dihydroxylation of the double bond of vinyl epoxides and their derivatives (bromo derivatives, azido derivatives and vinyl aziridines) are presented herein. A significant diastereoselectivity was observed for the bromo derivatives, azido derivatives and N-protected vinyl aziridines, whereas vinyl epoxides and unprotected vinyl aziridines
A highly stereoselective conversion of α,β-epoxy esters to α-hydroxy esters. An efficient route to optically active α-hydroxyesters
作者:Kenji Otsubo、Junji Inanaga、Masaru Yamaguchi
DOI:10.1016/s0040-4039(00)96531-6
日期:1987.1
α,β-Epoxy esters were cleanly converted to α-hydroxy esters with retention of the configurations at the α-carbon atoms via MgI2-promoted regioselective oxirane ring-opening followed by tributyltin hydride-reduction.