Retro-aldol reactions of β-hydroxy ketones take place under rhodium catalysis, leading to regioselective formation of the corresponding rhodium enolates. The enolates react with aldehydes in situ to afford the corresponding aldol adducts in high yields.
Enolates were generated from α,β-epoxy sulfoxides using lithium dimethylcuprate as an electron-transfer reagent. The enolates were trapped with several electrophiles, in which aldehydes reacted with the generated enolates giving aldols in good yields with high regioselectivity.
[GRAPHICS]Highly chemo-, diastereo-, and enantioselective borohydride reduction of 2-substituted-1,3-diketones was achieved in the presence of the optically active beta -ketoiminato cobalt complex catalysts to afford the optically active 2-substituted-3-hydroxyketones. The present catalytic and enantioselective reduction could provide an alternative potential for preparation of optically active ant aldol-type compounds.
SATOH, TSUYOSHI;SUGIMOTO, ATSUSHI;ITOH, MASAYUKI;YAMAKAWA, KOJI, TETRAHEDRON LETT., 30,(1989) N, C. 1083-1086
作者:SATOH, TSUYOSHI、SUGIMOTO, ATSUSHI、ITOH, MASAYUKI、YAMAKAWA, KOJI
DOI:——
日期:——
SATOH, TSUYOSHI;SUGIMOTO, ATSUSHI;ITOH, MASAYUKI;YAMAKAWA, KOJI, BULL. CHEM. SOC. JAP., 62,(1989) N, C. 2942-2947
作者:SATOH, TSUYOSHI、SUGIMOTO, ATSUSHI、ITOH, MASAYUKI、YAMAKAWA, KOJI