Iridium‐Catalyzed Enantioselective Allylic Substitutions of Racemic, Branched Trichloroacetimidates with Heteroatom Nucleophiles: Formation of Allylic C−O, C−N, and C−S Bonds
作者:Madhawee K. Arachchi、Hien M. Nguyen
DOI:10.1002/adsc.202100575
日期:2021.9.7
branched allylic carbon-heteroatom bonds from racemic, secondary allylic trichloroacetimidates has been developed. The branched allylic substrates undergo dynamic kinetic asymmetric substitution reactions with a number of unactivated anilines and carboxylic acids as well as unactivated aromatic thiols in the presence of a chiral bicyclo[3.3.0]octadiene-ligated iridium catalyst. The allylic C−O, C−N
已经开发了一种广泛适用的方法,用于从外消旋、仲烯丙基三氯乙酰亚胺酯中区域和对映选择性构建支链烯丙基碳-杂原子键。在手性双环[3.3.0]辛二烯-连接的铱催化剂存在下,支化烯丙基底物与许多未活化的苯胺和羧酸以及未活化的芳族硫醇发生动态动力学不对称取代反应。以合成有用的产率和选择性获得含有烯丙基 C-O、C-N 和 C-S 键的产物。机理研究表明,铱催化的杂原子亲核试剂与烯丙基三氯乙酰亚胺酯底物通过外球亲核加成机制进行对映选择性取代反应。此外,手性二烯连接的铱催化剂可有效促进无环仲苯胺的不对称胺化。重要的是,这种催化铱方法能够使用烷基取代的烯丙基亲电试剂。