Effect of metal counterions on the stereoselectivity of aldol reactions used to assemble the seco acid backbone of erythromycin b
作者:Stephen F. Martin、Wen-Cherng Lee
DOI:10.1016/s0040-4039(00)73542-8
日期:1993.4
reactions of the enolates derived from the ketones 11, 15, and 19 with the aldehyde 2a depended upon whether the counterion was lithium or titanium. For lithiumenolates the stereoselectivity appeared to be controlled by the stereochemistry alpha to the carbonyl group of the aldehyde partner, whereas the stereochemistry at the α′-carbon of the enolate was important for the titanium enolate.