Synthetic studies on O-heterocycles via cycloadditions. Part 1. Photochemical (electron transfer sensitised) C-C cleavage of diaryloxiranes
作者:Paul Clawson、Patricia M. Lunn、Donald A. Whiting
DOI:10.1039/p19900000153
日期:——
with naphthalene-1,4-dicarbonitrile as sensitiser in the presence of electron deficient dipolarophiles leads, via a presumed carbonyl ylide, to various dihydro- and tetrahydro-furans. This chemistry is extended, for the first time, to an example with both aryl rings oxygenated, 2,3-bis(p-methoxyphenyl)oxirane, using anthracene-9,10-dicarbonitrile as sensitiser; in contrast to stilbene oxide, in this
The photochemistry of 2,3-bis(p-methoxyphenyl)oxirane: trapping of a C–C cleaved intermediate in an electron-transfer sensitised process
作者:Paul Clawson、Patricia M. Lunn、Donald A. Whiting
DOI:10.1039/c39840000134
日期:——
2,3-Bis(p-methoxyphenyl)oxirane (6) rearranges, with C–O cleavage, to the carbonyl compounds (8) and (9) on irradiation, direct or triplet sensitised, and thermally: in contrast C–C cleavage is observed with dicyanoanthracene as electron-transfersensitiser, and the resulting intermediate can be trapped by dipolarophiles in synthetically useful reactions.