Acyloxonium ions in the high-yielding synthesis of oxolanes from alditols, hexoses, and hexonolactones catalysed by car☐ylic acids in anhydrous hydrogen fluoride
✍ Scribed by Jacques Defaye; Andre´e Gadelle; Christian Pedersen
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 770 KB
- Volume
- 205
- Category
- Article
- ISSN
- 0008-6215
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✦ Synopsis
Treatment of o-glucono-l,S-or o-mannono-1,4-lactone with anhydrous hydrogen fluoride catalysed by formic or acetic acid yields 3,6-anhydro-o-glucono-and -o-mannono-1,4-lactone, respectively. Similarly, o-mannitol is converted into 1,4-anhydro-o-mannitol and subsequently into the 1,4:3,6-dianhydride, whereas o-giucitol forms exclusively the 3,danhydride and, on further reaction, I ,4:3,6_dianhydroo-glucitol. D-Ghrcose and 2-acetamido-2-deoxy-o-glucose are also converted into the corresponding 3,6anhydrides by reaction with hydrogen fluoride and formic acid. "C-N.m.r. spectroscopy indicates that the reactions involve intermediate dioxolanylium ions. * Dedicated to Professor Leslie Hough in the year of his 65th birthday. ' Carbohydrate Reactivity in Hydrogen Fluoride, Part 8. For Part 7, see Ref. 1.