The catalytic enantioselective nucleophilic borylation of ketimines is reported. A series of acyclic dialkyl ketimines reacted efficiently with bis(pinacolato)diboron in the presence of a copper(I)/chiral N-heterocyclic carbene catalytic system to furnish optically active α-amino tertiary boronates with high enantioselectivity (up to 99% ee). The products can be converted into peptidylboronic acid
报道了
酮亚胺的催化对映选择性亲核
硼酸化。在
铜(I)/手性N-杂环卡宾催化体系存在下,一系列无环二烷基
酮亚胺与双(
频哪醇)二
硼有效反应,提供具有高对映选择性(高达 99% ee)的光学活性 α-
氨基叔
硼酸酯. 产物可以转化为带有庞大
脂肪族取代基的肽基
硼酸衍
生物,这些化合物很难用其他方法合成。密度泛函理论计算表明,对映选择性决定步骤涉及识别前手性二烷基
酮亚胺的非共价相互作用,导致高效的对映歧视。