Pd(MeCN)2Cl2 enables the α-stereoselective catalytic synthesis of 2,3-unsaturated O-glycosides from O(3)-acylated glycals without the requirement for additives to preactivate either donor or nucleophile. Mechanistic studies suggest that, unlike traditional (η3-allyl)palladium-mediated processes, the reaction proceeds via an alkoxy-palladium intermediate that increases the proton acidity and oxygen
Pd(MeCN)2 Cl 2能够从O(3)酰化的糖中进行2,3-不饱和O-糖苷的α-立体选择性催化合成,而无需添加剂来预先激活供体或亲核试剂。机理研究表明,与传统的(η3-烯丙基)
钯介导的过程不同,该反应通过烷氧基-
钯中间体进行,该中间体增加了醇的质子酸度和氧亲核性。该方法以一系列合成用途的糖苷和糖缀合物的合成为例。