Efficient carbene transfer reactivity mediated by Fe(II) complexes supported by bulky alkoxides.

Herein we describe the stoichiometric and catalytic carbene-transfer reactivity of iron(II) alkoxide complexes with iodonium ylide precursors. Treatment of PhIC(CO 2 Me) 2 with styrene in the presence of catalytic amounts of several different Fe(OR) 2 (THF) 2 precursors results in efficient cyclopropanation for a variety of styrenes. Computational and reactivity studies suggest a novel remote metallocarbene/vinyl radical intermediate, Fe(OR) 2 (κ 2 -(OC(OMe)) 2 C), which could be responsible for the reactive nature of the catalyst.