The [3,3]‐Sigmatropic Allyl Cyanate–Isocyanate Rearrangement on Levoglucosenone Derivatives Stereoselectively Provides 4‐Deoxy‐4‐Aminosugars

The Ichikawa rearrangement of allyl cyanates obtained in situ from levoglucosenone-derived allyl carbamates allows the synthesis of unique 4-deoxy-4-amino-d-allose derivatives with complete chirality transfer in a metal-free three-step, one-pot manner.

Levoglucosenone is a fascinating carbohydrate-based building block obtained from renewable sources, and its use in organic synthesis for the obtainment of highly added-value compounds is particularly encouraged from a circular economy point of view. Herein, the allyl cyanate–isocyanate metal-free rearrangement is reported on the allyl carbamate derived from levoglucosenone. In the presence of O-, N-, and S-nucleophiles this rearrangement forms (4S)-carbamates, ureas, and carbamothioates in a regio- and stereoselective manner. The elaboration of the unsaturated adducts through dihydroxylation of the double bond after the rearrangement allows access to new, unique d-allo configured 4-deoxy-4-aminosugar derivatives.

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