Abstract:
Spontaneous hydrobromination of allyl chloride (AC) proceeds in the liquid phase (180–220 K, thermal effect ΔH= 17 kcal mor−1) to give 1-chloro-2-bromopropane; active centres produced by radiolysis at 77 K at the glass transition (87–95 K) initiate a chain addition reaction of HBr to AC to form 1-chloro-3-bromopropane (thermal effect Δ13.2 kcal mor−1). This is the first example of hydrobromination at matrix devitrification; a local brittle fracture of the irradiated sample of AC + HBr gives an autowave of chemical conversion spread over the sample.