PREPARATION OF 6 LEAD(II) DIALKOXIDES, X-RAY CRYSTAL-STRUCTURES OF [PB(MU-ETA-1-OCH2CH2OME)2]INFINITEY AND [PB3(MU-O-T-BU)6], AND HYDROLYSIS STUDIES

Six lead(II) dialkoxides prepared by alcoholyses of Pb[N(SiMe3)2]2are described: Pb(0–i–Pr)2(1), Pb(0–f–Bu)2(2), Pb(OCMe2Et)2(3), Pb(OCEt3)2(4), Pb(OCH2CH2OMe)2(5), and Pb(OCHMeCH2NMe2)2(6). All except 1 and 5 have good solubility in organic solvents. The compounds sublime or distill in the range 95-170 °C at 10-4Torr; only 5 decomposes during sublimation. Hydrolysis of 3 or 6 in THF gives 3PbO-H20, which is not converted to massicot or litharge (polymorphs of PbO) by refluxing the reaction slurry. However, the first-formed 3PbO-H20 is converted to litharge when 3 is hydrolyzed in the presence of 10 mol % of LiOCMe2Et and the resulting slurry is refluxed. Two compounds are completely structurally characterized: [Pb(μ,η1-OCH2CH2OMe)2]∞ (5) and [Pb,(η-0-f-Bu)6] (2). Compounds 5 and 1 are isostructural in the solid state. Crystal data for 5: monoclinic, C2/c, a = 11.411 (8) Å, b = 14.641 (6) Å, c = 6.278 (3) Å, β = 108.34 (5)°, V= 995.6 (9) Å3, T= 22 °C, Z = 4, and Dc= 2.384 g cm-3. Of the 3794 intensities measured, 1026 unique reflections withI> 3σ(I) yielded R(F0) = 0.0258 and RW(F0) = 0.0320. Crystal data for 2: trigonal (hexagonal axes), R3, a = b = 10.174 (2) Å, c = 29.491 (9) Å, V = 2643.6 (11) Å3, T= 22 °C, Z = 3, andDc= 1.998 gem-3. Of the 1566 intensities measured, 517 unique reflections with I> 3σ(I) yielded R(Fa) = 0.0504 and RW(F0) = 0.0592. © 1990, American Chemical Society. All rights reserved.