Suleman Muhammad, Qi Minghui, Xie Jianwei, Lu Ping, Wang Yanguang
Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China.
Org Biomol Chem. 2022 Mar 2;20(9):1900-1906. doi: 10.1039/d1ob02405a.
Herein, we report a C-H bond functionalization strategy for the construction of oxo- and aza-spirocyclic compounds from diazo compounds as coupling partners. Our method comprises sp C-H bond activation of arylacyl ammonium salts, followed by coupling with two types of cyclic diazo compounds 4-diazoisochroman-3-imines and 4-diazoisoquinolin-3-ones, respectively. The mechanism involves the formation of dual metal carbene intermediates with the breakage of oxidizing C-N bonds in arylacyl ammonium salts. The cascade C-H activation/annulation process gave a variety of novel spiro[indene-1,4'-isochromane]-3,3'(2)-diones and spiro[indene-1,4'-isoquinoline]-3,3'(2)-diones in good to excellent yields. Readily available starting materials, broad substrate scope, and operationally simple and mild reaction conditions are the prominent features of this method.
在此，我们报道了一种以重氮化合物作为偶联伙伴构建氧杂和氮杂螺环化合物的C-H键官能化策略。我们的方法包括芳酰基铵盐的sp C-H键活化，然后分别与两种环状重氮化合物4-重氮异苯并二氢吡喃-3-亚胺和4-重氮异喹啉-3-酮偶联。该机理涉及双金属卡宾中间体的形成以及芳酰基铵盐中氧化C-N键的断裂。级联C-H活化/环化过程以良好至优异的产率得到了多种新型螺[茚-1,4'-异苯并二氢吡喃]-3,3'(2)-二酮和螺[茚-1,4'-异喹啉]-3,3'(2)-二酮。易于获得的起始原料、广泛的底物范围以及操作简单温和的反应条件是该方法的突出特点。
