The Wohl degradation is a series of reactions that shorten an aldose chain by one carbon, it is almost the exact opposite of the Kiliani-Fischer synthesis. In this reaction the aldose aldehyde carbonyl group is converted into a nitrile. The resulting cyanohydrin loses HCN under basic conditions. Conversion of the aldehyde to a nitrile is accomplished by treatment of the aldose with hydroxylamine to form an oxime. Dehydration of the oxime with acetic anhydride yields the cyanohydrin. Draw curved arrows to show the movement of electrons in this step of the mechanism. Where "R" is used, it represents the rest of the sugar chain. Arrow-pushing Instructions H2Ň-OH о—с—н OH но -H H2N-OH но H H- OH OH H OH OH CH2OH ČH,OH

The Wohl degradation is a series of reactions that shorten an aldose chain by one carbon, it is almost the exact opposite of the Kiliani-Fischer synthesis. In this reaction the aldose aldehyde carbonyl group is converted into a nitrile. The resulting cyanohydrin loses HCN under basic conditions. Conversion of the aldehyde to a nitrile is accomplished by treatment of the aldose with hydroxylamine to form an oxime. Dehydration of the oxime with acetic anhydride yields the cyanohydrin. Draw curved arrows to show the movement of electrons in this step of the mechanism. Where "R" is used, it represents the rest of the sugar chain. Arrow-pushing Instructions H2Ň-OH о—с—н OH но -H H2N-OH но H H- OH OH H OH OH CH2OH ČH,OH

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter11: Reactions Of Alkyl Halides: Nucleophilic Substitutions And Eliminations

Section11.SE: Something Extra

Problem 79AP

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