Intramolecular cyclization of in situ generated adducts formed between thioamide dianions and thioformamides leading to generation of 5-amino-2-thiazolines and 5-aminothiazoles, and their fluorescence properties.

Reactions of thioamide dianions, derived from secondary N-arylmethyl thioamides using BuLi, with thioformamides followed by the addition of iodine to yield 5-amino-2-thiazolines are described. Treatment of the 5-amino-2-thiazolines with iodine leads to a highly efficient production of 5-aminothiazoles. When N,N-diarylthioformamides are employed in this process, fluorescent 5-N,N-diarylthiazoles are obtained.