B. Villaume et al., Serendipity in perfluorinated series: unexpected synthesis of 7-(perfluoroalkyl)-2,3-dihydro-5H-l,4-dioxepin-5-one, TETRAHEDR L, 42(12), 2001, pp. 2305-2306
Treatment of [2-(perfluoroalkyl)-1,3-dioxolan-2-yl]acetic acids with thiony
l chloride and a 48% HBr solution yields 7-polyfluoroalkyl-2,3-dihydro-5H-1
,4-dioxepine-5-one. The production of this unexpected entity is explained b
y a rearrangement mechanism proposed in this work. (C) 2001 Elsevier Scienc
e Ltd. All rights reserved.