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We report the deprotonation of a chiral nitrile and reaction of the resulting chiral organometallic species with a variety of electrophiles to give highly enantiomerically enriched 2-substituted nitrile products. The nitrile was treated with TMPMgCl and the resulting anion, an asymmetric alpha cyano Grignard species, was found to be configurationally stable at low temperature for a short time (half-life several minutes at −104 °C).

Chiral macrocyclic V(V) salen complexes 1a – f derived from macrocyclic ligands obtained by the reaction of 1 R ,2 R -(−) diaminocyclohexane/(1 R ,2 R )-(+)-1,2-diphenylethylenediamine with bis-aldehydes 2 and 3 were synthesized and used as efficient catalysts in asymmetric cyanation reactions. The V(V) catalysts demonstrated excellent performance (product yields and ees up to 99%) with potassium cyanide (KCN) and sodium cyanide (NaCN). The catalytic system also performed very well with a safer source of cyanide-ethyl cyanoformate to give cyanohydrin carbonates in excellent yield and ee (up to 97%). The V(V) macrocyclic salen complex 1b retained its performance at multi-gram level and was conveniently recycled for a number of times.

Various ionic liquids ( IL 1 – 9 ) based on N -methyl N′ -alkyl imidazolium salts were explored as catalytic media in cyanoethoxycarbonylation of various aldehydes. The study revealed that the alkyl chain length and counter ion of the ionic liquid are critical for the product yield. The highest product yield of cyanohydrin carbonate (up to 96%) was obtained with C 5 alkyl chain with Br − as counter ion ( IL 3 ). On the other hand PF 6 − as counter ion failed to catalyze the cyanoethoxycarbonylation reaction.

Chiral dimeric vanadium (V) salen complex (10 mol%) derived from 5,5-Methylene di-[( S,S )-{ N -(3- tert -butyl salicylidine)- N′ -(3′,5′-di- tert -butyl salicylidene)]-1,2-cyclohexanediamine] with vanadyl suphate followed by auto oxidation was used as efficient catalyst for enantioselective Strecker reaction of N -benzylimines with TMSCN at −30 °C. Excellent yield (92%) of α-aminonitrile and high chiral induction was achieved (ee up to 94%) in case of 2-methoxy substituted N -benzylimines in 10 h. The catalytic system worked well up to four cycles with retention of enantioselectivity.

Chiral macrocyclic V(V) salen complexes 1a – f derived from macrocyclic ligands obtained by the reaction of 1 R ,2 R -(−) diaminocyclohexane/(1 R ,2 R )-(+)-1,2-diphenylethylenediamine with bis-aldehydes 2 and 3 were synthesized and used as efficient catalysts in asymmetric cyanation reactions. The V(V) catalysts demonstrated excellent performance (product yields and ees up to 99%) with potassium cyanide (KCN) and sodium cyanide (NaCN). The catalytic system also performed very well with a safer source of cyanide-ethyl cyanoformate to give cyanohydrin carbonates in excellent yield and ee (up to 97%). The V(V) macrocyclic salen complex 1b retained its performance at multi-gram level and was conveniently recycled for a number of times.