Chlorination of cellulose with sulfuryl chloride in lithium chloride-dimethylacetamide and azidation of the products.

Abstract

Products containing chlorine and chlorosulfate groups were prepared by the chlorination of cellulose powder with sulfuryl chloride in a mixture of lithium chloride and N, N-dimethylacetamide in the presence of pyridine. The sodium iodide treatment of this product yielded chlorodeoxycellulose with a maximum d. s. of 1.8 by chlorine, which was introduced at C-6 and C-3. Chlorosulfate groups were rather stable to acidic or neutral water, but unstable in alkaline water and were converted into hydroxyl groups or cyclic sulfates. They were replaced by azide and chloride ions or converted into cyclic sulfates by the sodium azide treatment in N, N-dimethylformamide at temperatures of 20 to 70°C. The same treatment of the chlorination product at 90°C resulted in the replacement of chlorine by azide and that at 110°C gave a product with a high d. s. of 1.1 by azide.