Stereoselective synthesis of cyclopentanoids and cyclitol derivatives originated from polychlorinated norbornene systems

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2009
Gümüş, Ayşegül
Optically active polychlorinated norbornene systems are important starting compounds for the synthesis of many complex molecules. The synthetic strategy of this study mainly depends upon the enzymatic resolution of hydroxymethyl-substituted polychlorinated norbornene structures. The enantiomerically enriched acetoxymethyl derivatives were synthesized in high ee values by several lipases. The absolute configuration of tetrachlorinated norbornene system was determined by X-ray analysis. The second part of the thesis involves the ruthenium and cerium-catalyzed oxidation reactions of various polychlorinated norbornene derivatives to afford α-diketones. The regioselectivity of ruthenium catalyst was tested in polychlorinated norbornadiene systems. In the third part of the study, cyclopentanoid derivatives were synthesized in high chemical yield starting from enantio-enriched both tetra- and hexa-chlorinated norbornene derivatives. In the last part of the study, stereo- and regioselective synthesis of carbasugar systems which are potential glycosidase inhibitors were performed. Starting from enantio-enriched acetoxymethyl substituted tetrachloro norbornene system both carbasugar by cleavage of C1-C7 bond and ‘confused’ carbasugar by cleavage of C4-C7 bond were synthesized.

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Citation Formats
A. Gümüş, “Stereoselective synthesis of cyclopentanoids and cyclitol derivatives originated from polychlorinated norbornene systems,” Ph.D. - Doctoral Program, Middle East Technical University, 2009.