THERMAL AND PHOTOCHEMICAL-REARRANGEMENT OF 3-SUBSTITUTED 2-METHYLBENZOFURAN EPOXIDES AND THEIR VALENCE-ISOMERIC QUINONE METHIDES

Authors
ADAM W KAB G SAUTER M
Citation
W. Adam et al., THERMAL AND PHOTOCHEMICAL-REARRANGEMENT OF 3-SUBSTITUTED 2-METHYLBENZOFURAN EPOXIDES AND THEIR VALENCE-ISOMERIC QUINONE METHIDES, Chemische Berichte, 127(2), 1994, pp. 433-436
Citations number
16
Categorie Soggetti
Chemistry
Journal title
Chemische Berichte → ACNP
ISSN journal
00092940
Volume
127
Issue
2
Year of publication
1994
Pages
433 - 436
Database
ISI
SICI code
0009-2940(1994)127:2<433:TAPO32>2.0.ZU;2-7
Abstract
The dimethyldioxirane oxidation of the 3-substituted 2-methylbenzofura ns 1 [1a: 3(E)-styryl, 1b: 3-acetoxy, 1c: 3-(tert-butyldimethylsilylox y)] is reported. Only quinone methide 3a, none of the benzofuran epoxi des 2a-c, could be detected by H-1- and C-13-NMR spectroscopy at low t emperature (-30-degrees-C), which on photoisomerization led to chromen e 7a. The benzofuran-3-ones 5b, c and the alpha-diketone 6c are presum ably formed by thermal isomerization of the transient benzofuran epoxi des 2b, c and quinone methide 3c.