The Journal of Organic Chemistry

Rearrangements of 2-pyrones and pyran-2-thiones involving 1, 5-sigmatropic hydrogen shifts

WH Pirkle, WV Turner

文献索引：Pirkle,W.H.; Turner,W.V. Journal of Organic Chemistry, 1975 , vol. 40, # 11 p. 1617 - 1620

全文：HTML全文

被引用次数: 32

摘要

At elevated temperatures, 2-pyrones bearing hydrogen in the 6 position reversibly exchange substituents be-tween the 3 and 5 positions. Evidence is presented from oxygen-18 labeling experiments that the “migrations” actually occur via reversible electrocyclic ring opening to ketene aldehydes which undergo reversible [1, 5] sigmatro-pic shifts of the aldehydic hydrogen. Pyran-2-thiones undergo similar rearrangements and quantitatively afford ...