Picture of wind turbine against blue sky

Open Access research with a real impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs.

The Energy Systems Research Unit (ESRU) within Strathclyde's Department of Mechanical and Aerospace Engineering is producing Open Access research that can help society deploy and optimise renewable energy systems, such as wind turbine technology.

Explore wind turbine research in Strathprints

Explore all of Strathclyde's Open Access research content

Synthesis of peracetylated D-galactopyranosylidene dihalides

Praly, J P and Brendle, J C and Klett, J and Pequery, F (2001) Synthesis of peracetylated D-galactopyranosylidene dihalides. Comptes Rendus - Academie des Sciences Paris Serie 2 Chimie Fascicule C, 4 (7). pp. 611-617. ISSN 1387-1609

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Upon treatment with aluminium trichloride in absolute chloroform, beta -D-galactopyranose penta-O-acetate was converted in high yield into tetra-O-acetyl-beta -D-galactopyranosyl chloride. In the presence of N-bromosuccinimide in boiling carbon tetrachloride, homolytic substitution of the anomeric hydrogen atom in this beta -chloride occurred selectively to afford tetra-O-acetyl-1-bromo-beta -D-galactopyranosyl chloride, in admixture with minor amounts of tetra-O-acetyl-D-galactopyranosylidene chloride. Bromine substitution by fluorine took place with a low stereoselectivity in tetra-O-acetyl-1-bromo-beta -D-galactopyranosyl chloride when treated with 1.25 equiv silver fluoride in acetonitrile, whereas tetra-O-acetyl-beta -galactopyranosylidene fluoride could be prepared in 54% yield with 3.3 equiv AgF. The gem-difluoride could be deacetylated quantitatively. Upon treatment with 1,4-diazabicyclo[2.2.2] octane, peracetylated 1-bromo-beta -D-galactopyranosyl chloride underwent 1,2-elimination of hydrogen bromide to afford 2,3,4,6-tetra-0-acetyl-D-lyxo-hex-1-enopyranosyl chloride in 33 % yield. (C) 2001 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.