Reactivity of main-group–transition-metal bonds. Part 8. The kinetics of mercuration of compounds containing Group 4B elements bonded to manganese, iron, and molybdenum: effects of structure on reactivity

Abstract

The kinetics of cleavage by HgBr₂ of the main-group–transition-metal bonds in the following compounds are reported: [Mn(CO)₅(MR₃)](M = Sn, R = Et, Buⁿ, or C₆H₁₁; M = Si or Ge, R = Me); [Fe(cp)(CO)₂(MR₃)](M = Sn, R = Buⁿ or C₆H₁₁; M = Si or Ge, R = Me; cp =η-cyclopentadienyl); and [Mo(cp)(CO)₃(SnBuⁿ₃)Buⁿ₃]. The structure–reactivity patterns indicate that mercuration involves an S_E2(open) transition state. Mercury(II)bromide does not cleave the tin–transition-metal bonds in [Mn(CO)₅(SnPh₃)] or [Fe(cp)(CO)₂(SnPh₃)] but cleaves the phenyl–tin bonds in these compounds.