Synthesis and catalytic activity of N‐heterocyclic silylene (NHSi) iron (II) hydride for hydrosilylation of aldehydes and ketones

A novel silylene supported iron hydride [Si, C]FeH (PMe3)3 (1) was synthesized
by C (sp3)-H bond activation with zero-valent iron complex Fe (PMe3)4. Complex
1 was fully characterized by spectroscopic methods and single crystal X-ray
diffraction analysis. To the best of our knowledge, 1 is the first example of
silylene-based hydrido chelate iron complex produced through activation of the
C (sp3)H bond. It was found that complex 1 exhibited excellent catalytic activity
for hydrosilylation of aldehydes and ketones. The catalytic system showed
good tolerance and catalytic activity for the substrates with different functional
groups on the benzene ring. It is worth mentioning that, the experimental
results showed that both ketones and aldehydes could be reduced in good to
excellent yields under the same catalytic conditions. Based on the experiments
and literature reports, a possible catalytic mechanism was proposed.