Preparation of alkyl α- and β-d-glucopyranosides, thermotropic properties and X-ray analysis

Monohydrates of heptyl to decyl α-d-glucopyranosides as obtained from product mixtures of the Fischer glucosylation were crystallized from water at the Krafft point. The results of the single-crystal X-ray analysis of anhydrous α anomers and their monohydrates provide for a better understanding of crystal formation and stability of their hydrates. The preparation of alkyl β-d-glucopyranosides—without concomitant formation of α anomers as by-products—has been described. The thermotropic properties have been investigated for the α compounds and their monohydrates, and for the β-d-glucopyranosides.