(S)-Mandelic acid enolate as a chiral benzoyl anion equivalent for the enantioselective synthesis of non-symmetrically substituted benzoins
作者:Gonzalo Blay、Isabel Fernández、Belén Monje、Marc Montesinos-Magraner、José R. Pedro
DOI:10.1016/j.tet.2010.12.012
日期:2011.2
A strategy for the enantioselective synthesis of non-symmetrically substituted benzoins from (S)-mandelic acid and aromatic aldehydes has been developed. This strategy is based on a diastereoselective aldol reaction of the lithium enolate of the 1,3-dioxolan-4-one derived from (S)-mandelic acid and pivalaldehyde with aromatic aldehydes, which gives the corresponding aldols in good yields. Subsequent
已经开发了一种从(S)-扁桃酸和芳香醛对映体选择性合成不对称取代的安息香的策略。该策略基于衍生自(S)-扁桃酸和新戊醛的1,3-二氧戊环-4-一的烯醇锂与芳香族醛的非对映选择性醛醇缩合反应,从而以高收率得到了相应的醛醇。随后的作为MEM醚的羟基保护,二氧戊环环的碱性水解,α-羟基酸部分的氧化脱羧以及羟基的脱保护提供了具有高对映体过量的手性非对称取代的安息香。