CHLORINATION OF CHITIN WITH SULFURYL CHLORIDE UNDER HOMOGENEOUS CONDITIONS

Chitin was chlorinated with sulfuryl chloride under homogeneous condit ions in LiCl-N,N-dimethylacetamide. Chlorodeoxychitins were obtained i n the reactions at temperatures from -30 to 70 degrees C. The regiosel ective replacement of C-6 hydroxyl groups with chlorine atoms occurred in the reaction for 4 h at -20 degrees C while C-3 hydroxyl groups we re also replaced above 0 degrees C when the molar ratio of sulfuryl ch loride to the repeating unit of chitin was 15. The yield of chlorodeox ychitin decreased from 90 to 60% with the rise in reaction temperature from -30 to 60 degrees C and dropped to 27% at 70 degrees C. All the chlorodeoxychitin samples were soluble in formic acid. (C) 1997 Elsevi er Science Ltd.