Three Coordinated Organoaluminum Cation for Rapid and Selective Cyanosilylation of Carbonyls under Solvent‐Free Conditions

Abstract

The well-defined three coordinated electronically unsaturated cationic organoaluminum complex [({(2,6-iPr2C6H3N)P(Ph2)}2N)AlMe]+[MeB(C6F5)3]− (1), has been utilized to catalyze the cyanosilylation of aldehydes and ketones under mild and solvent-free conditions. Moreover, catalyst 1 showed high chemoselective cyanosilylation of aldehydes over ketones, nitriles and olefins. The multinuclear NMR investigations revealed that cyanosilylation proceeds via Lewis adduct formation between 1 and TMSCN thereby activating TMSCN (Si-CN bond) followed by nucleophilic attack of the carbonyl oxygen at the Si center of the activated silane and formation of the product.