Tris(dialkylamino)benzylphosphonium bromides - Phosphonium salts with three N atoms configurated nearly planar

Tris(dialkylamino)benzylphosphonium bromides [(R2N)(3)PCH2C6H5]Br-+(-) (R: Me, Et, n-Pr, n-Bu) have been obtained by the reaction of the corresponding tris(dialkylamino)phosphines with benzylbromide in good yields. The compou nds crystallize as colorless solids from acetonitrile or methylene chloride after addition of diethylether. The corresponding tris(dialkylamino)-benzy lphosphonium tribromides have been prepared by treating of the simple bromi des with equimolar quantities of elemental bromine. The orange-red precipit ates have been recrystallized from the same solvents by addition of diethyl ether. In all compounds investigated the crystal structure analyses showing three N atoms with a nearly planar configuration.