Trimesityllead Derivatives, Mes₃PbR, R=Me, CH₂Ph, CH₂CH═CH₂, CH₂C≡CH, Me₃Ge Including Structural Analysis of Monomeric Mes₃PbCl and Attempted Formation of Mes₃PbSnMe₃

Abstract

Trimesityllead-R derivatives (R=methyl, benzyl, allyl, propargyl, and trimethylgermyl) have been synthesized from the salt elimination reaction between trimesityllleadlithium and RX. The germanium derivative is the first alkylgermanium derivative of lead. The spectroscopic properties of the compounds are reported, along with the single crystal structure of trimesityllead chloride which reveals that the Pb atom has a distorted tetrahedral coordination with an average Pb-C bond length of 2.234A, and C-Pb-Cl bond angles much smaller than the C-Pb-C angles. This is the first structurally characterized monomeric organolead halide. The Pb-Cl bond length of 2.61A is considerably shorter than the Pb-Cl bond length found in other oligomeric or polymeric organolead chlorides and significantly longer than recent theoretical estimations. Attempts to synthesize the trimethyltin derivative resulted in migration of a mesityl group to form mesityltrimethyltin as the only isolated compound.

Key Words:

• Trimesitylleadlithium
• group 14 derivatives
• chloride structure