High 1,5-Anti Stereoinduction in Boron-Mediated Aldol Reactions of Methyl Ketones
作者:Luiz C. Dias、Rosana Z. Baú、Márcio A. de Sousa、J. Zukerman-Schpector
DOI:10.1021/ol026968c
日期:2002.11.1
[reaction: see text] We report herein a very efficient and synthetically useful 1,4-anti-1,5-anti boron-mediatedaldolreaction of a chiral alpha-methyl-beta-alkoxy methyl ketone with achiral aldehydes.
Convenient syntheses of (2R,3S,4R)-3-(tert-butyldimethylsilanyloxy)-2,4-dimethyl-5-oxopentanoic acid methoxymethylamide from methacrolein. Preparation of C1–C7 and C17–C24 fragments of (+)-discodermolide
作者:Billy W. Day、Cyrous O. Kangani、Kwasi S. Avor
DOI:10.1016/s0957-4166(02)00261-6
日期:2002.6
Two new highly stereoselective routes to (2R,3S,4R)-3-(tert-butyldimethylsilanyloxy)-2,4-dimethyl-5-oxopentanoic acid methoxymethylamide, an important intermediate in natural product synthesis, are described. Both schemes are considerably shorter and less expensive than methods previously reported. The title compound was then converted to direct precursors of C1–C7 and C17–24 fragments of the potent