ChemInform Abstract: Oligosaccharide Analogues of Polysaccharides. Part 9. Synthesis and Thermolysis of Acetylenosaccharide-Derived 1,2-Dialkynylbenzenes.

✍ Scribed by J. XU; A. EGGER; B. BERNET; A. VASELLA

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 34 KB
• Volume: 28
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199705246

✦ Synopsis

Oligosaccharide Analogues of Polysaccharides. Part 9. Synthesis and Thermolysis of Acetylenosaccharide-Derived 1,2-Dialkynylbenzenes.

-Title compounds of type (III) and (IV) are prepared by coupling of glucosylalkynes with 1,2-diiodobenzene. The outcome is found to depend on the present O-protecting groups as well as the nature of added amine. Optimal yield (¿ 85%) of the dialkynylated product (IVb) is obtained by stepwise coupling. Thermolysis of the dialkyne (IVa) gives the naphthalene (V) and the rearranged isomer (VI). The debenzylated analogue (VII) of (V) represents a new type of C-glycosides. The mono-glucosylated derivative (VIII) also undergoes cycloaromatization to the naphthalene (IX) on heating, whereas the fully unprotected analogue of (IV) undergoes decomposition instead of cycloaromatization. -(XU,