Borane-Catalyzed Stereoselective C–H Insertion, Cyclopropanation, and Ring-Opening Reactions
作者:Ayan Dasgupta、Rasool Babaahmadi、Ben Slater、Brian F. Yates、Alireza Ariafard、Rebecca L. Melen
DOI:10.1016/j.chempr.2020.06.035
日期:2020.9
Lewis acidic boranes have been shown to be effective metal-free catalysts for highly selective reactions of donor-acceptor diazo compounds to a range of substrates. The reactions of α-aryl α-diazoesters with nitrogen heterocycles indole or pyrrole selectively generate C3 and C2 C–H insertion products, respectively, in good to excellent yields even when using unprotected indoles. Alternatively, benzofuran
已经证明路易斯酸性硼烷是供体-受体重氮化合物与一系列底物高度选择性反应的有效无金属催化剂。α-芳基α-重氮酸酯与氮杂环吲哚或吡咯的反应分别选择性地生成C3和C2 C–H插入产物,即使使用未保护的吲哚,其收率也良好至优异。备选地,苯并呋喃,茚和烯烃底物仅产生具有α-芳基α-二重氮酯的环丙烷化产物,而与呋喃的反应导致开环。全面的理论计算已用于解释这些反应的不同反应性和高选择性。总的来说,这项工作证明了α-芳基α-重氮酸酯与(杂)环和烯烃的选择性无金属催化反应。这个简单