Effects of the trichloromethyl group in displacement reactions of some 3-O-tosyl-1,2-O-trichloroethylidene-α-d-galacto- and -gluco-furanose derivatives

✍ Scribed by Hüseyin Anil; Levent Yüceer

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 244 KB
• Volume: 123
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(83)88486-9

✦ Synopsis

Previous investigations *Z have shown that the nucleophilic displacement reactions of the 3-0-tosyl derivative of 1,2:5,6-di-O-isopropylidene-a-D-glucofuranose with charged nucleophiles are very slow (e.g., the reaction with aide in N,N-dimethylformamide is complete only after 15 days at 11.5"). This is attributed to the repulsion of the approaching nucleophile by the lone-pair electrons of the 1,2-0-isopropylidene ring-oxygens and also to steric hindrance by the en&-methyl group of the same ring3. The effect of trichloromethyl groups in similar reactions is now considered 'Trichloroethylidene Acetals, Part II. For Part 1, see ref. 1.