Metalloporphyrin Catalyzed C-H Amination

Direct C-H bond functionalization to form C-N bonds via nitrenoid insertion is one of the most effective strategies to construct N-functionalized molecules of importance. In this context, metalloporphyrins have established themselves as effective catalytic systems for such transformation, following an outer-sphere pathway. In the past few years C(sp(3))-H bond amination has progressed in leaps and bounds, tackling the chemo-/regioselectivity issue not only in small molecules but also in complex molecules through late-stage functionalization, furnishing valuable N-scaffolds. It is only very recently that the biocatalytic approach with metalloporphyrin-based enzymes has emerged as a promising research area demonstrating very good regio- and stereoselectivity toward the development of environmentally benign C-H amination processes. Importantly, the progress in aromatic C-H bond amination has also gained prominence lately under metalloporphyrin catalysis. This review covers development achieved to date in metalloporphyrin-catalyzed C-H amination, including the very nascent biocatalytic C-H bond nitrenoid insertion, in addition to providing an insight on the mechanistic aspects as well.