Highly enantioselective transfer hydrogenation of quinolines catalyzed by gold phosphates: achiral ligand tuning and chiral-anion control of stereoselectivity.

A little gold goes a long way: as little as 0.01 mol % of chiral gold phosphate is sufficient to afford the asymmetric transfer hydrogenation of quinolines with high stereoselectivity (up to 98 % ee). The achiral ligands on gold were found to have considerable effect on the catalytic efficiency.