Synthesis of molecular lead–pnictogen compounds including [Pb4(SbSiiPr3)6], the first structurally characterised compound with a lead–antimony bond

Abstract

The first structurally characterised lead(II) antimony compound with a chemical bond between lead and antimony, [Pb₄(SbSiiPr₃)₆] (3), was obtained by the reaction of iPr₃SiSb-(SiMe₃)₂ with PbCl₂ in Et₂O at 0 °C. The Pb₄Sb₆ cage structure can be described as a Pb₄Sb₄ heterocube where two SbSiiPr₃ edges are replaced by (SbSiiPr₃)₂. The average Pb–Sb bond length is 297.7 pm. The heterocubane compounds [PbESi-tBu₂Ph]₄ (E = P, As) were obtained from the reactions of Pb{N(SiMe₃)₂}₂ with tBu₂PhSiEH₂.