Generation of Lithium Enolates Accelerated by Lithium Trifluoromethanesulfonate. Application to the Selective 1,4-Chiral Induction in the Aldol Reaction of<i>t</i>-Butyl δ-Hydroxy Carboxylates
The presence of lithium trifluoromethanesulfonate accelerates the enolate formation from t-butyl δ-hydroxy carboxylates with lithium diethylamide. The reaction of the resulting enolates with ketones or benzaldehyde affords the corresponding α,δ-syn aldol adducts stereoselectively.