[(PPh3)2NiCl2]-Catalyzed C-N Bond Formation Reaction via Borrowing Hydrogen Strategy: Access to Diverse Secondary Amines and Quinolines

Commercially available [(PPh3)(2)NiCl2] was found to be an efficient catalyst for the mono-N-alkylation of (hetero)aromatic amines, employing alcohols to deliver diverse secondary amines, including the drug intermediates chloropyramine (5b) and mepyramine (5c), in excellent yields (up to 97%) via the borrowing hydrogen strategy. This method shows a superior activity (TON up to 10000) with a broad substrate scope at a low catalyst loading of 1 mol % and a short reaction time. Further, this strategy is also successful in accessing various quinoline derivatives following the acceptorless dehydrogenation pathway.

Automated summary

Commercially available [(PPh3)(2)NiCl2] has been found to be an efficient catalyst for the mono-N-alkylation of (hetero)aromatic amines, delivering diverse secondary amines, including drug intermediates, in excellent yields (up to 97%) via the borrowing hydrogen strategy. This method shows superior activity with a broad substrate scope at a low catalyst loading and short reaction time, and is also successful in accessing various quinoline derivatives through the acceptorless dehydrogenation pathway.