Iron(II) Complexes Bearing Chelating Cyclopentadienyl-N-Heterocyclic Carbene Ligands as Catalysts for Hydrosilylation and Hydrogen Transfer Reactions

A series of piano-stool iron(II) complexes bearing bidentate cyclopentadienyl-functionalized N-heterocyclic carbene ligands (Cp-NHC)Fe(CO)I (Cp = substituted and unsubstituted cyclopentadienyl) have been prepared upon reaction with Fe(CO)4I2 and characterized by spectroscopic and crystallographic methods. The 16-electron half-sandwich compound (Cp*-NHC)FeCl (Cp* = η5-C5Me4) has been synthesized by using FeCl2 as precursor material. The new iron complexes displayed good catalytic activity in catalytic transfer hydrogenation of ketones and hydrosilylation reactions.