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

Abstract

Abstract 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.