On the synthesis and structure of monoaryllead and diaryllead acetates RPb(OCOCH3)3 and R2Pb(OCOCH3)2

Article abstract of DOI:10.1016/S0022-328X(96)06477-7

Anhydrous monoaryllead triacetates ArPb(OAc)₃ (Ar = Ph, p-Tolyl, o-Tolyl, 2,5-Xylyl; OAc = OCOMe) were prepared by arylation of Pb(OAc)₄ with ArSn(C₄H₉-n)₃ in the presence of Hg(OCOCF₃)₂. The procedure was adapted for the synthesis of diaryllead diacetates Ar₂Pb(OAc)₂ (Ar = Ph, p-Tolyl, o-Tolyl, p-ClC₆H₄, o-ClC₆H₄) and afforded products with higher purity than other procedures. The crystal structures of PhPb(OAc)₃, Ph₂Pb(OAc)₂ and (o-Tolyl)₂Pb(OAc)₂ were determined by X-ray diffraction. PhPb(OAc)₃ and (o-Tolyl)₂Pb(OAc)₂ are monomeric. The pentagonal bipyramid around Pb in PhPb(OAc)₃, like the trapezoidal bipyramid around Pb in (o-Tolyl)₂Pb(OAc)₂, is heavily distorted, the OAc groups being unsymmetrically chelating. Lead in Ph₂Pb(OAc)₂ is in a distorted octahedral environment. One OAc group is bridging, linking the molecular units to infinite chains, the other OAc group is symmetrically chelating. IR, ¹H, ¹³C and ²⁰⁷Pb NMR spectroscopic data are reported. The structures of p-TolPb(OAc)₃, o-TolPb(OAc)₃ and 2,5-XylPb(OAc)₃ are inferred to be similar to that of PhPb(OAc)₃, and the structure of (o-ClC₆H₄)₂Pb(OAc)₂ is inferred to be similar to that of (o-Tolyl)₂Pb(OAc)₂.