Amidinato Isopropylmethylamidosilylene‐Catalyzed Hydroboration of Carbonyl Compounds

Abstract

Abstract This study describes the use of an amidinato isopropylmethylamidosilylene [LSiN(Me) i Pr] ( 1 , L=PhC(N t Bu) 2 ) to catalyze hydroboration of carbonyl compounds. Compound 1 (loading: 5–10 mol%) was shown to be an efficient catalyst for the chemoselective hydroboration of aldehydes (average yield=97 %, average TOF=8.8 h −1 ) and ketones (average yield=97 %, average TOF=1.7 h −1 ) with pinacolborane (HBpin) in C 6 D 6 at 90 °C to form borate esters. Mechanistic studies show that the Si lone pair electrons on 1 and the B vacant p orbital of HBpin activates the C=O double bond of aldehydes and ketones, the intermediates of which undergoes hydroboration to yield borate esters and regenerate compound 1 .