THERMAL-DECOMPOSITION OF TERT-BUTYL BROMIDE AND TERT-BUTYL IODIDE IN SHOCK-WAVES

The thermal decomposition reactions of t-butyl bromide and t-butyl iodide were studied in shock waves in the temperature range 760-1050 K using UV absorption spectroscopy. Both molecules eliminate hydrogen halide in a unimolecular fourcenter reaction t-C4H9Br --> i-C4H8 + HBr (1a) t-C4H9I --> i-C4H8 + HI. (1b) Combination of the measured rate constants with earlier low temperature results leads to the expressions k(1a) = 10(14.4 +/- 0.2)exp[-(180 +/- 3) kJ mol-1/RT]s-1 (between 505 K and 1050 K) and k(1b) = 10(13.9 +/- 0.2)exp[-(164 +/- 3) kJ mol-1/RT]s-1 (between 465 K and 1020 K).