Hexofuranurono-6,3-lactone preparation

Rauter and coworkers demonstrated that C-5-aIkylidene derivatives 112 of D-hexofuranurono-6,3-lactone can be obtained by Wittig olefination of the a-ketolactone 111 (Scheme 32) [160]. The related a-methylene lactone 114 was prepared in three steps from 3,6-anhydro-l,2-0-isopropylidene-a-D-j y/ )-5-hexulo-furanose 113 via Wittig reaction and aUylic oxidation. 

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