Photochemical 2 + 2 Cycloaddition of Arenecarboxylic Acid Esters to Furans and 1,3-Dienes. 2 + 2 Cycloreversion of Oxetanes to Dienol Esters and Ketones

Article abstract of DOI:10.1021/jo00262a032

Methyl benzoate and other simple arenecarboxylic acid esters have been found to undergo 2 + 2 photochemical cycloaddition at the carbonyl group to furans and certain 1,3-dienes.These additions afford mixtures of oxetanes and their 2 + 2 cycloreversion products: 4-aryl-4-alkoxy-1,3-butadienyl formates and acetates (from furan oxetanes) and dienyl aldehydes and ketones (from cyclic 1,3-dienes).