N-Allyloxycarbonyl derivatives of D-glucosamine as promotors of 1,2-trans-glucosylation in Koenigs–Knorr reactions and in Lewis acid catalyzed condensations

Abstract

The use of suitably blocked D-glucosamine derivatives possessing the N-allyloxycarbonyl protective group of the amino function represents potential new routes to 1,2-trans-glucosylations. Both 3,4,6-tri-O-acetyl-2-N-allyloxycarbonyl-2-amino-2-deoxy-α-D-glucopyranosyl bromide (2) and 1,3,4,6-tetra-O-acetyl-2-N-allyloxycarbonyl-2-amino-2-deoxy-β-D-glucopyranose (3) could be used in Koenigs–Knorr reactions or Lewis acid catalyzed condensations, respectively. Glucosides of simple alcohols and disaccharides were synthesized in good to excellent yields. The N-allyloxycarbonyl protective group was, moreover, easy to remove with Pd(0) complexes, thus affording, after acetylation, the corresponding N-acetyl-β-D-glucosamine glucosides under very smooth conditions.