A mechanistic study of the photochemistry of carbohydrate p-toluenesulfonates

Article abstract of DOI:10.1080/07328309608005422

Photolysis of 1,2:3,4-di-O-isopropylidene-6-O-(p-tolylsulfonyl)-α-D-galactopyranose (5) in methanol under nitrogen in the presence of sodium hydroxide or diazabicyclo[2.2.2]octane (3, DABCO) produces toluene and 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose (6) Electron transfer from DABCO or hydroxide ion to singlet excited 5 to generate a radical anion is the first step in this reaction. The radical anion rapidly fragments to give the p-tolylsulfonyl radical (2) and deprotonated 6, which accepts a proton from the solvent. The p-tolylsulfonyl radical (2) then abstracts a hydrogen atom from the solvent to give p-toluenesulfinic acid, a compound that is converted to the p-toluenesulfinate anion (8) under the basic reaction conditions. Photolysis of 8 completes the reaction sequence by forming toluene.

Full text of DOI:10.1080/07328309608005422

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Journal of Carbohydrate Chemistry
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A Mechanistic Study of the
Photochemistry of Carbohydrate p-
Toluenesulfonates
a
b
a b
a
R. J. Berki , E. R. Binkley , R. W. Binkley
, D. G. Hehemann ,
a
a
D. J. Koholic & J. Masnovi
a
Department of Chemistry , Cleveland State University , Cleveland,
Ohio, 44115
b
Center for Carbohydrate Study , 19 Hawthorne Dr., Oberlin, Ohio ,
44074
Published online: 22 Aug 2006.
To cite this article: R. J. Berki , E. R. Binkley , R. W. Binkley , D. G. Hehemann , D. J. Koholic &
J. Masnovi (1996) A Mechanistic Study of the Photochemistry of Carbohydrate p-Toluenesulfonates,
Journal of Carbohydrate Chemistry, 15:1, 33-40, DOI: 10.1080/07328309608005422
To link to this article: http://dx.doi.org/10.1080/07328309608005422
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