Cyanomethylation of imines enabled by a mild deprotonation of acetonitrile using a combination of TMSCF3 and CsF

β-Amino acids are important structural units in chemistry and biology. Herein we reported a method to synthesize β-amino nitriles, the crucial synthetic precursor to β-amino acids. By using a nucleophilic base-complex, in situ generated from TMSCF3 and CsF, addition of acetonitrile to a series of aromatic imines offered the corresponding β-amino nitriles in excellent yields. Moreover, other electron withdrawing group bearing methyl group could be deprotonated to produce a good nucleophile under this mild conditions.