Photolysis of nitro-β,γ alkenes: Nitro-2,5-cyclohexadienes

Article abstract of DOI:10.1016/S0040-4020(01)88368-X

Photolysis of 3-fluoro-4-methyl-, 3-chloro-4-methyl-, and 3,4-dimethyl-4-nitro-2,5-cyclohexadienyl acetate, in methanol, gives 3-fluoro-4-methyl-, 3-chloro-4-methyl-, and 3,4-dimethyl-4-hydroxy-2,5-cyclohexa-dienyl acetate, respectively. The replacement of nitro by hydroxyl is stereospecific. Photolysis of 1,4-dimethyl-4-nitro-2,5-cyclohexadienyl acetate in methanol gives 1,4-dimethyl-4-hydroxy-2,5-cyclohexadienyl methyl ether. Photolysis in ether gives 1,4-dimethyl-4-hydroxy-2,5-cyclohexadienyl acetate, with retention of configuration, and p-xylene. Photolysis of 1,4-dimethyl-4-nitro-2,5-cyclohexadienyl methyl ether in methanol gives 1,4- dimethyl-4-hydroxy-2,5-cyclohexadienyl methyl ether, with retention. Photolysis in ether gives 1,4-dimethy 1-4-hydroxy-2,5-cyclohexadienyl methyl ether, with retention, and p-xylene.