Highly Diastereoselective Formation of Ruthenium Complexes for Efficient Catalytic Asymmetric Transfer Hydrogenation

Jumping Josiphos! Ruthenium cis ‐dichloro complexes with matched chiral diphosphane and aminopyridine ligands (see structure) are easily obtained by a one‐pot reaction of [RuCl 2 (PPh 3 ) 3 ] with a Josiphos diphosphane and racemic 1‐substituted 1‐(pyridin‐2‐yl)methanamine ligands. These complexes are highly active catalysts for the transfer hydrogenation of ketones, affording turnover frequencies of up to 70 000 h −1 at 60 °C and ee  values up to 99 %.