Cu-Catalyzed Couplings of Heteroaryl Primary Amines and (Hetero)aryl Bromides with 6-Hydroxypicolinamide Ligands
作者:David J. Bernhardson、Daniel W. Widlicka、Robert A. Singer
DOI:10.1021/acs.oprd.9b00195
日期:2019.8.16
chemoselectivity and rate. The use of K2CO3 as the base enabled selective C–N coupling of aryl bromides over aryl chlorides with 2–5 mol % Cu at 80–120 °C. With K3PO4 as the base, aryl chlorides are capable of undergoing C–N coupling, though 5–10 mol % Cu is required at 120–130 °C. Members of the ligand family are straightforward to prepare in one step from 6-hydroxypicolinic acid and the corresponding
已经确定了6-羟基吡啶甲酸酰胺配体家族是Cu催化的杂芳基溴化物和氯化物与杂芳基伯胺的偶联的有效支撑配体。C–N偶联是在80–120°C的DMSO或环丁砜中,以2-10 mol%CuI和支持配体的K 2 CO 3或K 3 PO 4为碱进行的。发现碱的强度对化学选择性和速率有影响。使用K 2 CO 3作为碱,可以在80–120°C的条件下,以2–5 mol%的Cu在芳基氯上进行芳基溴的选择性C–N偶联。含K 3 PO 4作为基础,芳基氯化物能够进行C–N偶联,尽管在120–130°C下需要5–10 mol%的Cu。配体家族的成员可以直接一步一步由6-羟基吡啶甲酸和相应的苯胺制备。