A series of chiral iridium(I) (1-3)e complexes of bioxazoline fused imidazole derived N-heterocyclic carbene (NHC) ligands successfully carried out asymmetric transfer hydrogenation of α, β-unsaturated ketones in good to excellent yields (ca. 36-91%) and in low enantioselectivites (ca. 5-31% ee) at 1 mol % of the catalyst (1-3)e loading in the presence of NaOH as a base in i-PrOH at 75°C in 3 hours of reaction time. The iridium(I) (1-3)e complexes were synthesized directly from the bioxazoline fused imidazole derived NHC precursors namely {(3R,7R)-3,7-di-R-2,3,7,8-tetrahydrodioxazolo[3,2-c:3',2'-e]imidazol-4-ium trifluoromethanesulfonate, R = s- butyl (1 d), i-butyl (2 d), i-propyl (3 d)} by the treatment with {(COD)IrCl} 2 (COD = 1,5-cyclooctadiene) in presence of t-BuOK as a base at room temperature. The chiral bioxazoline fused imidazole NHC ligand precursors (1-3)d were synthesized from the commercially available optically pure amino acids by a sequence of reactions without requiring any chiral resolution.

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