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Incidence and avoidance of stereospecific 1,2-ethylthio group migration during the synthesis of ethyl 1-thio-α-l-rhamnopyranoside 2,3-orthoester

✍ Scribed by France-Isabelle Auzanneau; David R. Bundle

Publisher
Elsevier Science
Year
1991
Tongue
English
Weight
815 KB
Volume
212
Category
Article
ISSN
0008-6215

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✦ Synopsis

The 1,Zmigration of an ethylthio group with inversion of configuration at the C-l and C-2 atoms was observed during the attempted preparation of 2,3-orthocster derivatives of ethyl l-thio-a-L-rhamnopyranoside. The rearrangement leading to the formation of methyl 2-thio-@glucopyranosides could be avoided by preparing the orthoester in DMF rather than in acetonitrile and by using a controlled amount of acid catalyst.

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