Perfluorophenylboronic acid 1c catalyzes the direct stereoselective addition of alcohol nucleophiles to deactivated peracetylated d-galactal to give 2-deoxygalactosides in 55-88% yield with complete α-selectivity. The unprecedented results reported here also enable the synthesis of disaccharides containing the 2-deoxygalactose moiety directly from the deactivated peracetylated d-galactal. This convenient and metal-free
全氟苯基
硼酸1c催化将醇亲核试剂直接立体选择性加成到失活的过乙酰化d-半
乳糖上,以55-8%的收率得到2-deoxygalactosides,具有完全的α-选择性。这里报道的空前的结果还使得能够直接从失活的过乙酰化的d-半
乳糖合成包含2-脱氧半
乳糖部分的二糖。这种方便且无
金属的糖基化方法可与多种醇亲核试剂作为受体配合使用,并能耐受多种官能团,而不会形成Ferrier副产物,也无需大量过量的亲核试剂或添加剂。该方法对于合成多种α-2-脱氧半
乳糖苷可能是有用的。