Glycosyl thiocyanates having hydroxyl groups protected with acetyl or benzoyl groups react readily at− 40° C with Grignard reagents to afford the corresponding alkyl or aryl thioglycosides in good yields. Monosaccharide derivatives having the SCN grouping at other positions form under similar conditions thioethers. Axial thiocyanates do not react. Elevated temperatures induce side reactions leading to mercaptans.
