A Highly Chemoselective Cobalt Catalyst for the Hydrosilylation of Alkenes using Tertiary Silanes and Hydrosiloxanes

The hydrosilylation of alkene substrates
bearing additional functionalities
is difficult to achieve using earth-abundant catalysts and has not
been extensively realized with both earth-abundant transition metals
and tertiary silanes or hydrosiloxanes. Reported herein is a well-defined
bis­(carbene) cobalt­(I)-dinitrogen complex for the efficient, catalytic
anti-Markovnikov hydrosilylation of terminal alkenes, featuring a
broad substrate scope. Alkenes containing hydroxyl, amino, ester,
epoxide, ketone, formyl, and nitrile groups are selectively hydrosilylated
in this reaction sequence. Multinuclear NMR studies of reactive intermediates
gave insights into the mechanism.