Alkyl D-glycoside prodn. from sugar and alcohol

Prodn. of alkyl D-glycosides of formula (I) comprises reacting a sugar of formula (II) with an alcohol of formula (III) in a solvent in the presence of a Lewis acid, provided that the solubility of (II) in the solvent is less than 5 wt.%: R1 = 6-22C alkyl or 6-22C hydrocarbyl contg. 1-4 ethylenic double bonds, opt. substd. on different C atoms by 1-3 substits. selected from OH, halogen and CF3; R2 = H or, when R6=H, CH2OH; R = C'H-C"H(OH)-, where Z = H or alkali(ne earth) metal and n = the valence of Z, provided that the OH gp. of R is on the beta side of the ring when R6 is bonded to C' and that R6 is on the alpha side of the ring when R6 is bonded to C"-, (b) CH2OH; or (c) H when R2 = CH2OH when R6 is bonded to C" or (ii) H when R6 is bonded to C', provided that: (1) when R6 = H, then R1 and the OH gp. alpha to R2 are on the beta side and the other OH gps. are on the alpha side; and (2) when R6 = CH2OH, then either R1 is on the alpha side and R6 and the other OH gps. are on the beta side, or R1 and the OH gp. alpha to R are on the beta side and the OH gp.alpha to R2 is on the alpha side. Les glycosides d'alkyle de formule (CF DESSIN DANS BOPI) dans laquelle R1 est alkyle et R2 est l'hydrogène ou hydroxyméthyle, R étant CH-CH(OH) ont des propriétés tensioactives.