A Comparison Between Catalyst-Free and ZrOCl2•8H2O-Catalyzed Strecker Reactions for the Rapid and Solvent-Free One-Pot Synthesis of Racemic α-Aminonitrile Derivatives

A rapid, straightforward, and efficient method for the synthesis of racemic alpha-aminonitriles has been developed. This one-pot, three-component Strecker reaction of carbonyl compounds, amines and trimethylsilyl cyanide (TMSCN) proceeds in excellent yields in the presence of a catalytic amount of zirconium oxychloride octahydrate (ZrOCl2 center dot 8H(2)O) under solvent-free conditions at room temperature. The protocol is particularly convenient for both aliphatic and aromatic aldehydes, as well as cyclic ketones, in combination with primary and secondary amines. This method is also highly chemoselective. Mild reaction conditions, excellent yields, high chemoselectivity, operational simplicity, the absence of tedious separation procedures, clean reaction profiles, high atom-economy, as well as the inexpensive and environmentally benign catalyst are the key advantages of this protocol. This Strecker reaction has also been studied in the absence of any catalyst and proceeds with good yields. The overall outcomes of these reactions in the presence and absence of catalyst are compared in the present study.