Reaction of [(μ-RE)(μ-CO)Fe2(CO)6]− (E=S, Se) with N2CHCO2Me. Synthesis and characterisation of (μ-RE)[μ-η2-NNCH(R′)CO2Me]Fe2(CO)6 and (μ-PhSe)[μ-η1-NNCH(Me)CO2Me]Fe2(CO)6

Reaction of [M][(μ-RE)(μ-CO)Fe2(CO)6] (E=S, Se; M=Et3NH, Na) with N2CHCO2Me give the intermediate [M][(μ-RE)(μ-N2CHCO2Me)Fe2(CO)6] (II). Action of II with counterion Et3NH+ yields neutral complexes (μ-RE)(μ-η2-NNCH2CO2Me)Fe2(CO)6 (1, RE=ButS; 2, RE=PhS; 3, RE=PhSe). Treatment of II (MNa) with MeI affords (μ-RE)[μ-η2-NNCH(Me)CO2Me]Fe2(CO)6 (4, RE=ButS; 5, RE=PhS). In the case of RE=PhSe, the reaction of II with MeI gives two isomers, (μ-PhSe)[μ-η2-NNCH(Me)CO2Me]Fe2(CO)6 (6) and (μ-PhSe)[μ-η1-NNCH(Me)CO2Me]Fe2(CO)6 (7). The structure of complex 7 has been determined by single-crystal X-ray diffraction technique.