Reactions of (SiMe _2)(GeMe _2) doubly bridged biscyclopentadiene with iron carbonyl and tungsten carbonyl

摘要

Thermal treatment of (SiMe _2)(GeMe _2)(C _5H _4) _2 (1) with Fe(CO) _5 in refluxing xylene provided the normal doubly bridged biscyclopentadienyl diiron tetracarbonyl complex (SiMe _2)(GeMe _2)[(η ~5- C _5H _3)Fe(CO)] _2(μ-CO) _2 (2) and the degermylated product (SiMe _2)[(η ~5-C _5H _4)Fe(CO)] _2(μ-CO) _2 (4), together with a novel complex (SiMe _2)(η ~5-C _5H _3) (η ~5:η ~1-C _5H _3)[(GeMe _2)Fe(CO) _2][Fe(CO) _2)] (3) containing an Fe-Ge bond, whose formation was accompanied by migration of bridging GeMe 2 group from the ligand to iron atom. Similar treatment of 1 with W(CO) _6 afforded the tungsten analogue of compound 4, (SiMe _2)(η ~5-C _5H _3)(η ~5: η ~1-C _5H _3)[(GeMe _2)W(CO) _3][W(CO) _3)] (6) and the degermylated product (SiMe _2)[(η ~5-C _5H _4)W(CO) _3] _2 (7). A plausible mechanism for formation of 3, and 6 was proposed. The crystal structures of 3, and 6 were determined by X-ray crystallography.