Theoretical insights of iron(II)–carbene complexes Cp(CO)(L)Fe [dbnd]CHR, L = CO, PMe 3

Abstract

Density functional theory has been used to study the geometries, properties and reactivity of the iron(II)–carbene complexes Cp(CO)(L)Fe CHR, L = CO, PMe 3, R = Me, OMe, ph, CO 2Me. Calculation results confirm that the iron–carbene complexes have two types of geometries: the Fe–C(carbene) bonds of the iron–carbene complexes A, D, E, and H (R = Me, CO 2Me) show a strong double-bonded character, and thus the Fe–C(carbene) bonds of the complexes B, C, F, and G (R = OMe, ph) show a strong single-bonded character. The Fe–C(carbene) bonds, and the iron and carbon atoms of Fe–C(carbene) bonds are the reactive center for the iron–carbene complexes. The geometry, electronic structure, and frontier orbitals (HOMO and LUMO) are discussed in detail.