The cyclohexadienyl radicals (CHR) with both methyl and isopropyl substitutions are formed in the atmospheric oxidation of cyclohexadiene-type terpenes through hydrogen abstraction by OH radical. In this Letter, theoretical study is carried out on the reactions of O₂ with c-C₆H₇ and 2-methyl-5-isopropyl-, 2-isopropyl-5-methyl, and 1-isopropyl-4-methyl-CHRs under the atmospheric conditions. Calculations show that the reaction of c-C₆H₇ forms benzene and the reactions of three CHRs forms p-cymene + HO₂ with almost unit yield. The reaction of c-C₆H₇ is much different to that of c-C₆H₆-OH.

中文翻译：

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^大气中O ₂^{形成环己二烯基自由基的机理和命运。理论研究}

具有甲基和异丙基取代基的环己二烯基（CHR）在环己二烯型萜烯的大气氧化中，通过OH自由基夺氢而形成。在这封信中，对O ₂与c -C ₆ H ₇和2-甲基-5-异丙基-，2-异丙基-5-甲基和1-异丙基-4-甲基-CHRs的反应进行了理论研究。在大气条件下。计算表明，反应C ^ -C ₆ ħ ₇形式苯和三个CHRS形式的反应p -cymene + HO ₂几乎单元产量。c -C的反应₆ H ₇与c -C ₆ H ₆ -OH有很大不同。