Traut's Reagent. A useful reagent for converting primary amine functional groups into free sulfhydryl groups, Synonyms:-2-Iminothiolane HCl; 2-IT; Dihydro-2-(3H)-thiophenimine hydrochloride; Dihydro-2-(3H)-thiophenimine HCl, CAS Number:-4781-83-3, Purity:-G90% by NMR, 1g.