Studies with heteroaromatic amines. A new route to 2-azolylamino-2- thiazolin-4-ones

Abstract

Heteroaromatic chloroacetamides 3a-c on treatment with potassium thiocyanate afforded the thiazolylaminothiazolines 6a-c via intermediacy of 4a-c and 5a-c. Compounds 6a-c condensed with dimethylformamide dimethylacetal (DMFDMA) to yield the Z-enamines 7a-c. The enamines 7a and 7b could be converted into the enamines 8a-e and 9a,b on treatment with amines. However, reacting 10c with morpholine afforded 11b. Compounds 9a,b, as well as 9c, were also obtained on reacting 6a-c with triethyl orthoformate and piperidine in DMF. The structures of 6a and 11b were confirmed by X-ray crystal structure determination.