The enantioselective synthesis of α-hydroxy esters by ruthenium-catalyzed 1,2-addition of arylboronic acids to tert-butyl glyoxylate is described. The use of RuCl2(PPh3)3 with (R,R)-Me-BIPAM gave optically active mandelic acids of up to 99% ee. Addition of a fluoride salt such as potassium fluoride (KF) or caesium fluoride (CsF) was effective for achieving high enantioselectivities.
描述了通过
钌催化的芳基
硼酸对叔丁基乙酰醛的1,2加成实现α-羟基酯的对映选择性合成。使用RuCl2(PPh3)3与(R,R)-Me-BIP
AM可以获得光学活性的一般酸,其对映体过量可高达99%。加入
氟化盐,如
氟化
钾(KF)或
氟化铯(CsF),对于实现高对映选择性是有效的。