NEW PLUMBYLENES AND A PLUMBYLENE DIMER WITH A SHORT LEAD-LEAD SEPARATION

The diarylplumbylene R2Pb: (3), R = 2-tBu-4,5,6-Me3C6H, and the rearra nged alkylarylplumbylene RR'Pb:, R = 2,4,6-tBu(3)C(6)H(2), R' = CH2C(C H3)(2)-3,5-tBu(2)C(6)H(3), were synthesized and characterized by NMR a nd UV/vis spectroscopy, as well as by X-ray crystallography, Treatment of 3 with the disilylplumbylene R-2'' Pb:, R '' = Si(SiMe3)(3), furni shed the heteroleptic plumbylene RR '' Pb: (8), which, in the solid st ate, forms the plumbylene dimer RR '' PbPbRR '' (9), The X-ray structu re analysis of 9 reveals a trans-bent angle of 46.5 degrees and a Pb . .. Pb separation of 3.37 Angstrom, the shortest observed so far betwee n the lead atoms of two plumbylenes.