KINETICS OF REACTIONS OF SILICON COMPOUNDS .3. GASPHASE UNIMOLECULAR THERMAL DECOMPOSITION OF 2,2-DIFLUOROETHYLMETHYL-DIFLUOROSILANE

The gas-phase thermal decomposition of 2,2- difluoroethylmethyldifluorosilane into vinyl fluoride and methyltrifluorosilane, at temperatures from 182° to 246° and at pressures from 20 to 186 torr, is kinetically of the first order. The reaction is homogeneous, and is unaffected by the addition of nitric oxide and cyclohexene. The first-order rate constant is independent of pressure, and is given by: log10k(sec. -1) = (11.32 ± 0.16) - (32,540 ± 360)/4.576T It is concluded that the reaction is unimolecular and proceeds by a four-centre β-fluorine elimination similar to that found in other β- fluoroalkylsilicon compounds.