AbstractThe 13C NMR spectra of N‐acetyl‐D‐glucosamine (1) and chitobiose (2), monomer and dimer of chitin, were assigned and used to assign the 13C NMR spectra of chitin in lithium thiocyanate and in LiCl/dimethylacetamide solutions. The dissolution of chitin in formic acid was studied. IR, 13C and 1H NMR spectra show that dissolution occurs by a reaction of formic acid with chitin with the formation of formyl chitin as a statistical derivative of chitin. 13C NMR spectra of diformyl‐ and diacetylchitin were also assigned to characterize these regular polymers.