Half‐Sandwich Iron Chalcogenopropargylcarbonato Complexes as CO‐Releasing Molecules

ABSTRACT Interaction of iron chalcogenides (μ‐E x )[CpFe(CO) 2 ] 2 (E = S; x = 2–4, E = Se, x = 1) with propargyl chloroformate (ClCO 2 CH 2 C≡CH) in diethyl ether yielded iron(II) chalcogenopropargylcarbonato complexes CpFe(CO) 2 ECO 2 CH 2 C≡CH (E = S ( 1 ), Se ( 2 )). These complexes have been characterized by elemental analysis, UV–Vis, IR, and 1 H‐ and 13 C{ 1 H}‐NMR spectroscopy and single‐crystal x‐ray diffraction techniques. Further, the suitability of complexes 1 and 2 as CO‐releasing molecules (CORMs) for the administration of carbon monoxide has been studied. CO gas is released upon irradiation of THF solution of these complexes in the presence of hemoglobin.