Preparation of chitin-p-toluenesulfonate and deoxy(thiocyanato) chitin

✍ Scribed by Y. Morita; Y. Sugahara; A. Takahashi; M. Ibonai

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 363 KB
• Volume: 30
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(94)90132-5

✦ Synopsis

Chitin-p-toluenesulfonate(tosyl-chitin)

was prepared homogeneously in lithium chloride-N,N-dimethylacetamide (LiC1/DMAc). In this solvent system, the side reaction of O-acetylation often occurred by solvolysis of p-toluenesulfonyl(tosyl) chloride. The utilization of strong base either triethylamine or 4-dimethylaminopyridine, leads to highly tosylated chitin, with minimal incorporation of an O-acetyl group. Similar results were found in the substitution of N-methylpyrroridone (NMP) for DMAc. Chitin-4(methylamino)butylate was obtained with a pyridine catalyst. The degree of tosylation increased with increasing amount of tosyl chloride and became constant above 1. Tosyl-chitin obtained at high reaction temperature was highly chlorinated. The tosyl-chitin with high degree of substitution was readily soluble in various polar organic solvents such as dimethylsulfoxide (DMSO) and N,N-dimethylformamide (DMF). By X-ray analysis, it was observed that the crystallinity of tosyl-chitin became low as the reaction proceeded. Treating tosyl-chitin with potassium thiocyanate in DMSO produced deoxy(thiocyanato)chitin.