Browsing by Author "Frey, Henry M."

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    Photolysis of Cycloheptanon
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (07), 1974) Frey, Henry M.; Mautner, Gillian N.
    The photochemical decomposition of cyclohcptanonc lias been studied in the gas phase as a function of pressure, temperature and wavelength. The major products arc carbon monoxide, hcx-l-cnc, cyclohexane and hcpt-6-enal. Quantum yields of the hydrocarbons and aldehyde were determined at 313 nm and 100'C over a range of ketone pressures. The results indicate that the hydrocarbons have a common precursor and that they arc produced by a higher energy pathway than the aldehyde. A mechanism involving a triplet state intermediate is suggested.
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    Thermal Ummolecular Reactions of Vinvlcvelnl . Isopropenylcyclobutane
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74 (07), 1978) Frey, Henry M.; Pottinger, Ruth
    The thermal decomposition of vinylcyclobutane proceeds by two pathways both of which are homogeneous first order processes. One reaction channel (k1) yields butadiene and ethylene, the other (k2) cyclohexene. Arrhenius equations have been obtained for both pathways from rate constants determined in the temperature range 296 to 366°C, viz: log k1/s–1= 14.87 ± 0.07 –(212,200 ± 800) J mol–1/RTln 10, log k2/s–1= 13.86 ± 0.13 –(203,500 ± 1500) J mol–1/RT ln 10. The thermal decomposition of isopropenylcyclobutane has been reinvestigated and found to be analogous to the vinyl compound. Arrhenius parameters have been obtained for its two modes of decomposition. All the reactions appear to be true unimolecular transformations. The potential energy surfaces for these decompositions and the back reactions are discussed.
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    Thermal unimolecular reactions of vinylcyclobutane and isopropenylcyclobutane
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74 (07), 1978) Frey, Henry M.; Pottinger, Ruth
    The thermal decomposition of vinylcyclobutane proceeds by two pathways both of which are homogeneous first order processes. One reaction channel (k1) yields butadiene and ethylene, the other (k2) cyclohexene. Arrhenius equations have been obtained for both pathways from rate constants determined in the temperature range 296 to 366°C, viz: log k1/s–1= 14.87 ± 0.07 –(212,200 ± 800) J mol–1/RTln 10, log k2/s–1= 13.86 ± 0.13 –(203,500 ± 1500) J mol–1/RT ln 10. The thermal decomposition of isopropenylcyclobutane has been reinvestigated and found to be analogous to the vinyl compound. Arrhenius parameters have been obtained for its two modes of decomposition. All the reactions appear to be true unimolecular transformations. The potential energy surfaces for these decompositions and the back reactions are discussed.