Acetic Anhydride–Acetic Acid as a New Dehydrating Agent of Aldoximes for the Preparation of Nitriles: Preparation of 2-Cyanoglycals

Abstract

Glycals, 1,2-unsatrated carbohydrates, are versatile building blocks for the synthesis of various scaffolds. Despite their potential to serve as suitable precursors in diversity-oriented synthesis, 2-cyanoglycals are less explored in terms of their synthesis and derivatization. Herein, we report a combination of Ac₂O and AcOH as new and efficient dehydrating agent of aldoximes for the synthesis of 2-cyanoglycals. In comparison to the conventional dehydrating system of Ac₂O-base (such as NaOH, NaOAc and K₂CO₃), the current protocol provides superior yields and faster reaction rates. The scope and limitations of the dehydrating system are investigated.

Key words

aldoximes - 2-cyanoglycals - nitriles

• References and Notes

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