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A simple, fast and efficient synthesis of 3-phosphorylated benzoxaboroles using the Pudovik reaction is reported. A number of diverse 3-(dialkoxyphosphoryl)-1-hydroxy-3H-2,1-benzoxaboroles were synthesised in 70–86% yield. Interesting hydrogen bond features were observed in the crystal lattice of the 5-chlorinated 3-bis(benzyl­oxy)phosphoryl derivative with both inter- and intramolecular C–H···O hydrogen bonds. Additionally, linear chains of intermolecular O–H···O hydrogen bonds were observed.

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. Catalytic Asymmetric Transfer Hydrogenation (ATH) of aromatic alkyl ketones has been investigated using transition metal complexes and new derivatives of monotosylated unsymmetrical vicinal diamine ligands using sodium formate as the hydrogen source, in water and methanol. Chiral secondary alcohols were obtained with excellent enantioselectivity (>95% ee) and conversion of ketones (>95%) with [Rh(Cp*)Cl2]2 and ligand 4 as a catalyst. Enantioselectivity was found to be slightly higher with the use of methanol as a solvent for ATH of ketones with sodium formate as the hydrogen source compared to water as a solvent and was found to be consistent with all the ketones investigated. The reaction mixture is homogeneous in methanol unlike in water, where substrate and product are insoluble in water and form separate phase, sodium formate being soluble in water. The activity and enantioselectivity obtained for ATH of ketones using [Rh(Cp*)Cl2]2 and unsymmetrical vicinal diamine ligand as catalyst was comparable with the C2 symmetric benchmark ligands like TsDPEN ((1R,2R)-N-(p-tolylsulfonyl)-1,2-diphenylethylene-diamine), and TsCYDN ((1R,2R)-N-(p-tolylsulfonyl)-1,2-cyclohexyl,diamine) under similar reaction conditions. To the best of our knowledge, this is first example of the ATH of ketones with good activity and high enantioselectivity with [Rh(Cp*)Cl2]2 and unsymmetrical vicinal diamine ligands as catalyst systems.

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.

Asymmetric transfer hydrogenation of various cyclic imines proceeded efficiently with water/methanol co-solvent media in 20 min with excellent yields and enantioselectivities by employing Rh–TsDPEN catalyst and sodium formate as a hydrogen donor. The role of the co-solvent in enhanced productivity of the reaction was investigated by DFT. The mechanism for ATH of the imines has been discussed on the basis of the DFT study.

Catalytic asymmetric transfer hydrogenation of aromatic alkyl ketones has been investigated using [Ru(p-cymene)Cl2]2 and new derivatives of β-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%). Asymmetric transfer hydrogenation of ketones has been investigated using [Ru(p-cymene)Cl2]2 and β-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%).

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.

1-Substituted 6,7-dimethoxy-3,4-dihydroisoquinolines (I) and (III) are used as substrates in the title reaction.