1,3-Dipolar Cycloadditions of Heterocycles 1. Cycloadditions of C-Benzoyl-N-Phenylnitrone to Furan

Article abstract of DOI:10.1007/BF00899256

A frontier orbital treatment of furan suggests its possible reactivity in 1,3-dipolar cycloadditions with dipoles posessing low lying LUMO's, such as nitrones, especially those with electronwithdrawing substituents.By the reaction of C-benzoyl-N-phenylnitrone 1a with an excess of furan at 60 deg C the monocycloadduct 2a, two biscycloadducts 4 and 5 and further reaction products of nitrone such as azoxybenzene 8, diketoamide 9a, benzoanilide 10a, benzoic acid 11a and phenyl glyoxylic acid 12 were isolated.The cycloaddition of C-(4-bromobenzoyl)-N-phenylnitrone 1b with furan is also reported. - Keywords: Cycloaddition of nitrone; 1,3-Dipolar cycloaddition; Frontier orbital treatment; Furan