Verfahren zur Herstellung von Trialkylplumbiden und von ?nsymmetrischen Bleitetraalkylverbindungen

摘要

1,220,039. Alkali metal trialkyl plumbides; tetra-alkyl lead. E. I. DU PONT DE NEMOURS & CO. 20 March, 1969 [22 March, 1968], No. 14820/69. Heading C2J. Alkali metal trialkyl plumbides are prepared by contacting a tetra-alkyl lead in which each alkyl group contains 1-6 carbon atoms and an alkali metal in a normally liquid, polar aprotic medium at a temperature between the freezing point and boiling point of the medium, or the decomposition temperature of the medium or of the tetraalkyl lead, whichever is lower. Each alkyl group has preferably 1-4 carbon atoms and at least one mole of the alkali metal per mole of the tetraalkyl lead is used, the reaction temperature being from 15‹ C. to 60‹ C. The aprotic medium may be hexamethylphosphoramide, hexamethylphosphoramide dissolved in an aromatic hydrocarbon solvent, an ether which forms a blue solution when contacted with the alkali metal or an ether having a hydrocarbon dissolved therein which forms a charge transfer complex with the alkali metal. The alkali metal trialkyl plumbides may be used for preparing unsymmetrical tetraalkyl lead compounds by contacting the plumbide in an aprotic medium with at least 1 mole per mole of plumbide of an alkylating agent of the formula R1X wherein X is a displaceable anion and R1 is an alkyl group of 1-14 carbon atoms and being different from at least one alkyl group of the plumbide and recovering the unsymmetrical tetraalkyl lead from the reaction mass.