Asymmetric transfer hydrogenation (ATH) of imines has been performed with variation in formic acid (F) and triethylamine (T) molar ratios in water. The F/T ratio is shown to affect both the reduction rate and enantioselectivity, with the optimum ratio being 1.1 in the ATH of imines with the Rh-(1S,2S)-TsDPEN catalyst. Use of methanol as a cosolvent enhanced reduction activity. A variety of imine substrates have been reduced, affording high yields (94-98%) and good to excellent enantioselectivities (89-98%). In comparison with the common azeotropic F-T system, the reduction with 1.1/1 F/T is faster.

Asymmetric transfer hydrogenation of various cyclic imines proceeded efficiently with H2O/MeOH (1 : 1, v/v) co-solvent media in 20 min with excellent yields and enantioselectivities by using Rh–TsDPEN catalyst and HCOONa as a hydrogen donor.

A bio-catalyzed N-formylation reaction of different amines has been developed using ethyl formate as a formylating agent. This protocol provides a facile and convenient strategy featuring mild reaction conditions, high efficacy, a broad substrate scope and recyclability of lipase. This method also works on a large scale in high yield.

Catalytic asymmetric transfer hydrogenation of aromatic alkyl ketones has been investigated using [Ru(pcymene)Cl 2 ] 2 and new derivatives of b-amino alcohols synthesized from (S)-(-)-lactic acid and mandelic acid as ligands. Chiral secondary alcohols were obtained with good to excellent conversion (60-90%) and moderate to good enantioselectivities (40-86%).

New unsymmetrical vicinal diamine ligands with systematic variation in the regio and stereo positions in the amine and sulphonamide groups were synthesized from cheap starting material such as norephedrine.