LEWIS ACID-BASE STUDIES OF TRIORGANOGALLIUM COMPOUNDS WITH ORGANOPHOSPHINES

The relative Lewis acidities of the series of triorganogallium compoun ds GaR3 (R = Me, Et, CH2CMe3, CH2SiMe3, CH2CMe2Ph, C6H2Me3) toward the common Lewis base HPPh2 and the relative Lewis basicities of a series of organophosphines which incorporate an acidic hydrogen HPRR' (PRR' = PPh2, P(C6H11)(2), PEt2, P(H)(C(6)Hr(11)) toward the common Lewis ac id Ga(CH2CMe3)(3) have been investigated and compared. Cryoscopic mole cular weight data permitted an evaluation of the equilibrium constant for the dissociation. of each of the adducts. The P-31 NMR spectral da ta, which were consistent with the molecular weight data, were also us ed to study the relative rates of hydrocarbon elimination reactions to form (R2GaPRR')(2).