The reaction of α-phenethyl radicals with 1,4-benzoquinone and 2,6-di-tert-butyl-1,4-benzoquinone

The absolute rate constant for 1,4-benzoquinone (BQ) irreversibly trapping α-phenethyl radicals (3) has been determined as 4.4×106 M−1 s−1 at 43 °C using acyclic cis azoalkane 9c as a radical precursor. These reactants afford the hydroquinone mono ether 4 at 30 °C but a mixture of products at elevated temperature. 2,6-Di-tert-butyl-1,4-benzoquinone (DTBQ) also reacts with 3 but the cyclohexadienone products are thermally labile.

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