Donor free stibenium cation as an efficient cyanosilylation catalyst.

The synthesis of novel stibenium cations and their catalytic application in cyanosilylation of carbonyl compounds have been described. Treatment of chlorostibine L 1 SbCl [L 1 = 1,2-C 6 H 4 {N(CH 2 t Bu)} 2 ] (2) with 1 equiv. of AgOTf and AgSbF 6 resulted in the formation of donor free L 1 SbOTf ( 3 ) and [L 1 Sb] + [SbF 6 ] - ( 4 ), respectively. Among these three compounds, 4 exhibits excellent catalytic activity towards the cyanosilylation of aldehydes and ketones.