Temperature dependence of the disproportionation/combination ratio for H + t-C4H9 and of the orientation of H atom addition to iso-C4H8

Abstract

The reaction between hydrogen atoms and isobutene has been investigated under conditions where [H][i-C₄H₈] in the temperature range 20–328 °C at an argon pressure of 6.6 Torr in a discharge-flow apparatus. Two ratios of rate constants have been determined, log (k₂/k₁)= 0.47 ± 0.33–16.6 ± 2.6 kj mol^–1/(2.3RT), and k₅/k₆= 3.55 ± 0.24, independent of temperature. (Error limits are 95% confidence limits.) H + i-C₄H₈→ t-C₄H^*₉(1), H + i-C₄H₈→ CH₃C₃H₆(2), H + t-C₄H₉→ H₂+i-C₄H₈(5), H + t-C₄H₉→ i-C₄H^*₁₀(10).

The stoichometry of the overall reaction is discussed.