Synthesis and reactivity of the cycloheptatrienyl-bridged bimetallic complexes [M(CO)3(μ-η6: η1-C7H7)M'(CO)2(η-C5R5)](M = Cr, Mo or W; M' = Fe or Ru; R = H or Me)

“Electronic Lock” in Chromiumtricarbonyl Complex of Cycloheptatrienyltin

The fast sigmatropic [1,5]-Sn migration in cycloheptatrienyl(triphenyl)tin is effectively locked in the chromiumtricarbonyl complex. A much slower [1,3]-Sn + [1,2]-Cr diatropic rearrangement was detected by spin saturation transfer NMR.