Gram-scale synthesis and efficient purification of 13C-labeled levoglucosan from 13C glucose

13C‐Labeled levoglucosan has been synthesized and purified in good yield, and on the gram scale in one step from commercially available 13C glucose. This one‐step protocol uses 2‐chloro‐1,3‐dimethylimidazolinium chloride that serves to selectively activate the anomeric carbon toward substitution reactions. The labeled glucose is then smoothly converted to the anhydroglucose. Purification is efficiently achieved on large scale by chromatography on silica gel. 13C‐Labeled levoglucosan has been synthesized and purified in good yield, and on the gram scale in one step from commercially available 13C glucose. This one‐step protocol uses 2‐chloro‐1,3‐dimethylimidazolinium chloride that serves to selectively activate the anomeric carbon group toward substitution reactions. The labeled glucose is then smoothly converted to the anhydroglucose. Purification is efficiently achieved on large scale by chromatography on silica gel.