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Glycosylidene Carbenes. Part 3. Synthesis of Spirocyclopropanes

✍ Scribed by Andrea Vasella; Christian A. A. Waldraff

Publisher: John Wiley and Sons
Year: 1991
Tongue: German
Weight: 698 KB
Volume: 74
Category: Article
ISSN: 0018-019X
DOI: 10.1002/hlca.19910740316

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✦ Synopsis

Thermolysis of the glycosylidene-derived 0 -benzylated diazirine 1 in the presence of N-phenylmaleimide (2), acrylonitrile (3), dimethyl fumarate (4), or dimethyl maleate (5) led in good yields to mixtures of the spirocyclopropanes 6/7, S l l , 12/13, and 12/13/16/17. The diastereoselectivity depends upon the alkene. The cycloaddition of 1 to 5 is not diastereospecific, in keeping with previous results. Deprotection of 12, 13, 16, and 17 yielded the tetrols 14, 15, 18, and 19, respectively. ') ' )

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