ABSTRACT
Azidoalkyl glycosides are popular intermediates in the syntheses of their amino counterparts, and also in preparation of glycoconjugates through click chemistry. 1,2 Several preparations of the per-O-acetate of the simplest compound in this series, 6-azidohexyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyranoside (3), were previously described, 3–7 but despite the obvious interest in glycoside 3, the compound has not been fully characterized. Here, we describe preparation of the title glucopyranoside 3, obtained in crystalline form for the first time, from the hitherto unknown 6-chlorohexyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyranoside (2). The latter was prepared by BF3·Et2O-catalyzed reaction of 6-chlorohexanol with 1 in a yield comparable to that of its bromo analog. 4 However, similar to 6-bromohexanol, 6-chlorohexanol is also commercially available but it is a several times less-expensive reagent. Our product 2 crystallized readily from the crude reaction mixture, and it was fully characterized. Its structure follows from the mode of synthesis, and was confirmed by the spectral data (NMR and MS).
