Terphenyl ligand stabilized lead(II) derivatives of simple organic groups:Characterization of Pb(R)C6H3-2,6-Trip(2) (R = Me, t-Bu, or Ph; Trip = C6H2-2,4,6-i-Pr-3), {Pb(mu-Br)C6H3-2,6-Trip(2)}(2), py center dot Pb(Br)C6H3-2,6-Trip(2) (py = pyridine), and the bridged plumbylyne complex [{W(CO)(4)}(2)(mu-Br)(mu-PbC6H3-2,6-Trip(2))]

The reaction between 1 equiv of the sterically encumbered lithium terphenyl Et2O.LiC6H3-2,6-Trip(2) and PbBr2 in diethyl ether afforded the organolead (II) halide compound {Pb(mu-Br)C6H3-2,6-Trip(2)}(2) (1) as orange crystals. Treatment of 1 with a stoichiometric amount of pyridine (py) gave the comp lex py.Pb(Br)C6H3-2,6-Trip(2) (2) as yellow needles. The addition of 1 equi v of methylmagnesium bromide, tert-butyllithium, or phenyllithium to 1 resu lted in the diorganolead(II) compounds Pb(R)C6H3-2,6-Trip(2) (R = Me, 3; t- Bu, 4; or Ph, 5) in good yield. The compounds 3 and 5 are the first stable, monomeric lead(II) derivatives involving the simplest alkyl and aryl group s Me and Ph. Reaction of 1 with W(CO)(5)THF did not yield the expected plum bylene complex (CO)(5)W{Pb(Br)C6H3-2,6-Trip(2)}. Instead, the bridged plumb ylyne species [{W(CO)(4)}(2)(mu-Br)(mu-Pb-C6H3-2,6-Trip(2))] (6) was obtain ed in low yield. All compounds were characterized by X-ray crystallography, H-1 and C-13 NMR, IR, and UV-vis spectroscopy. Pb-207 NMR spectra of 3-5 w ere also obtained. The results demonstrate the effectiveness of the terphen yl ligand in creating a protected cavity at a site in which normally unstab le moieties are stabilized against decomposition reactions.