Aldol condensations of ethyl 1,3-dithiolane-2-carsoxylate and ethyl 1,3-dithiane-2-carboxylate with chiral aldehydes. Exceptional diastereoface selectivity from two convenient acetate equivalents.
作者:Lee A. Flippin、Mark A. Dombroski
DOI:10.1016/s0040-4039(00)98596-4
日期:1985.1
Lithium enolates derived from the title esters show high diastereoface selectivity in their reactions with chiral aldehydes. The resulting 2,2-dithioaldols are desulfurized in good yield with Ni2B-H2 (EtOH, 20°C). With this mild desulfurization protocol, complete retention of stereochemical integrity was observed for all isolated aldols.