STABILITIES OF SOME STITUTED-PHENYL)4,4,5,5-TETRAMETHYL-1,3-DIOXOLANES RELATIVE TO THEIR CONJUGATE DIOXOLENIUM IONS, RADICALS AND CARBANIONS AS DETERMINED BY THERMODYNAMICS FOR HYDRIDE AND ELECTRON-TRANSFER INSOLUTION

A calorimetric method is described for the determination of the hydrid e affinities, Delta H-H-(R(+)) of seven dioxolenium ions from the titl e compounds and also tropylium, trityl and 9-phenyl xanthylium cations by hydride transfer to the carbocations from BH3CN-. Cyclic voltammet ric methods yield free energies for reduction of the cations to the co njugate radicals and to the carbanions. The Delta H-H-(R(+)) values co rrelate well with the first reduction potentials of the cations.