Novel thermal rearrangement reactions: rearrangement stereospecificity of complex [Fe_2(CO)_2(#mu#-CO)_2(#mu#-t-BuC_5H_3Me_2GeGeMe_2C_5H_3Bu-t)]

摘要

Thermal treatment of 1, 2-bis (3-tert-butylcyclopentadienyl)tetramethyldigermane with [Fe(CO)_5] in xylene gave the diiron complex [Fe_2(CO)_2(#mu#-CO)_2(#mu#-3-t-BuC_5H_3Me_2GeGeMe_2C_5H_3Bu-t-3)] 1 existing as a mixture of cis and trans isomers (1c and 1t) which were separated by preparative TLC. When the two isomers were heated in xylene the cis substrate (1c) rearranged to a trans product [Fe_2(CO)_4(#mu#-3-t-BuC_5H_3GeMe_2)_2] 2t, while the trans substrate (1t) afforded a cis product 2c. This indicates that the rearrangement reaction is stereospecific, which is consistent with previous results. Molecular structures of 1c, 1t, 2t and 2c were determied by X-ray diffraction.