Homogeneous manganese-catalyzed hydrogenation and dehydrogenation reactions

The development of novel and efficient earth-abundant metal catalysts as inexpensive and sustainable alternatives to noble-metal catalysts is a rapidly expanding and evolving field of sustainable chemistry. In this context, manganese is a “rising star” that has made great progress for catalytic hydrogenation and dehydrogenation reactions since the seminal work reported in 2016. This review aims to provide a comprehensive picture of homogeneous Mn-catalyzed hydrogenation and dehydrogenation reactions from the beginning of 2016 till now. Various reactions are described, including the hydrogenation of unsaturated C–O, C–N, and C–C bonds; dehydrogenation of C1-molecules; and catalytic cascade dehydrogenative transformation of alcohols. Particular emphasis is placed on mechanistic understanding of manganese catalysts in these reactions. The future development trend of this promising field is also discussed.