1056038-75-5Relevant academic research and scientific papers
Synthesis and properties of structural variants of the Si-Si bridged bis(cyclopentadienyl)tetracarbonyldiiron complexes: Modification on the bridge
Sun, Huailin,Liu, Qiuhua,Gu, Jianli,Zhang, Chengxun,Zhang, Zhensheng,Wang, Qiuchang
, p. 4505 - 4512 (2009/02/06)
A series of new structural variants of the Si-Si bridged bis(cyclopentadienyl)tetracarbonyldiiron complex (η5, η5-C5H4XC5H4)Fe 2(CO)4, where X = MeSi[μ-(CH2)4] SiMe (3), CH2SiMe2 (7), and SiMe2SiPh 2 (10), were synthesized and their properties studied with emphasis on the thermal rearrangement that had been demonstrated to occur when X = SiMe2SiMe2. It was found that the presence of the cyclic structure on the Si-Si bridge for complex 3 prohibited the thermal rearrangement, but oxygen insertion into the Si-Si bond took place under thermal conditions to give the new Si-O-Si bridged complex {η5, η5-C5H4MeSi(μ-O)[μ-(CH 2)4]SiMeC5H4]Fe2(CO) 4 (4). Using CH2SiMe2 as the bridging group in complex 7 also resulted in failure of the rearrangement because the C-Si bond could not be activated by the iron center. Complex 10, with the unsymmetric bridging group SiMe2SiPh2, underwent thermal rearrangement, producing the expected product cyclic-[(Me2Si- η5-C5H4)Fe(CO)2(Ph 2Si-η5-C5H4)Fe(CO)2]- (11) with two Si-Fe bonds. When the reaction was performed in the presence of P(OPh)3, incorporation of the phosphite ligand in the rearranged product took place, providing two regioisomers, cyclic-{(Me2Si- η5-C5H4)Fe(CO)[P(OPh)3](Ph 2Si-η5-C5H4)Fe(CO)2]- (12a) and cyclic-[(Me2Si-η5-C5H 4)Fe(CO)2(Ph2Si-η5-C 5H4)Fe(CO)[P(OPh)3]}- (12b), in a 1:1.8 ratio. The reaction of 10 with I2 led to Fe-Fe bond cleavage, affording di-iodide (η5η5-C5H4Me 2SiSiPh2C5H4)[Fe(CO) 2I]2 (13). The molecular structures of 3, 4, 7, 10, 11, and 13 have been determined by X-ray diffraction methods.
