Hydroboration of carbon dioxide enabled by molecular zinc dihydrides

Neutral molecular zinc(ii) dihydrides supported by N-heterocyclic carbene ligands bearing a pendant phosphine group were synthesized and then reacted with carbon dioxide to afford zinc diformates. The zinc dihydrides were found to be active catalysts for hydroboration of carbon dioxide under mild conditions, selectively giving boryl formate, bis(boryl)acetal, or methoxy borane compounds by changing the nature of the borane reductant.