Manganese‐Catalysed Transfer Hydrogenation of Quinolines under Mild Conditions.

Herein, an efficient methodology for the homogeneous manganese‐catalysed transfer hydrogenation of N‐heterocycles by using ammonia‐borane as a hydrogen source under mild reaction conditions is reported. Good to excellent isolated yields are achieved by applying a PNP manganese pincer complex. In the reaction, 1,2‐dihydroquinoline is detected as intermediate by NMR spectra analysis and deuterium labelling experiment. The catalytic reaction likely proceeded by an outer‐sphere pathway based on the bifunctional pincer complex. [ABSTRACT FROM AUTHOR]