Abstract 4, 4-Dimethoxy-2, 5-cyclohexadienones 9–14 were prepared from the corresponding hydroquinone monomethyl ethers by oxidation with thallium trinitrate in methanol. Irradiation of solutions of 9–13 in methanol with a broad band of UV light centered at 350 nm in a Rayonet reactor afforded 2-cyclopentenone derivatives 15–19 in moderate to excellent yields, whereas irradiation of 14 in methanol gave phenol 8 along with other ...
