Abstract:
New examples of the very rare class of iridium(I) Fischer
carbene complexes (FCCs) are reported from the facile transmetalation from
group 6 FCCs. Postcomplexation modification of either the carbene ligand or
the ancillary coligands results in a tunable IrI metal center, for unprecedented
application as a (pre)catalyst in a benchmark transfer hydrogenation reaction.
The introduction of an aminocarbene ligand with a pendant N-donor moiety
capable of hemilabile coordination yielded the best catalytic results with
turnover frequencies reaching 445 h−1 and requiring 0.1 mol % catalyst and 0.5 mol % base loading, respectively.
