Amidinato Isopropylmethylamidosilylene-Catalyzed Hydroboration of Carbonyl Compounds

This study describes the use of an amidinato isopropylmethylamidosilylene [LSiN(Me)iPr] (1, L=PhC(NtBu)(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 C6D6 at 90 degrees 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.

Automated summary

This study describes the use of an amidinato isopropylmethylamidosilylene catalyst for the efficient hydroboration of carbonyl compounds, resulting in the formation of borate esters. Mechanistic studies reveal the involvement of the Si lone pair electrons and the B vacant p orbital in the reaction process.