Enantioselective Construction of Axially Chiral Azepine-Containing P,N-Ligands from l-Alanine

• DOI: 10.1021/acs.orglett.1c02834
• Publication Date: 2021-10-01T15:01:20Z
• Authors: Jinlong Zhang; Zeng Gao; Jinlong Qian; Huameng Yang; Maosheng He; Gaoxi Jiang
• Keywords: Azepine; Diastereomer; Tsuji–Trost reaction; Chirality; Alanine; Axial symmetry; Axial Chirality

A family of axially chiral azepine-containing seven-membered cyclic P,N-ligands (named Indole-azepinap) have been prepared by using l-alanine as an original chirality source. The direct chromatographic separation two diastereomeric phosphine oxides on silica gel enabled these ligands to be easy available, allowing further structural and electronic modifications. Preliminary application Indole-azepinaps has demonstrated in a Pd-catalyzed asymmetric allylic alkylation with high yields moderate enantioselectivities.