Lewis acid-base studies of triorganogallium compounds with organophosphines

The relative Lewis acidities of the series of triorganogallium compounds 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 acid Ga(CH2CMe3)(3) have been investigated and compared. Cryoscopic molecular weight data permitted an evaluation of the equilibrium constant for the dissociation. of each of the adducts. The P-31 NMR spectral data, which were consistent with the molecular weight data, were also used to study the relative rates of hydrocarbon elimination reactions to form (R2GaPRR')(2).