Mannich reaction in the synthesis of n,s-containing heterocycles. 14. unexpected formation of thiazolo[3,2-a]pyridines in the aminoalkylation of n-methylmorpholinium 4-aryl-3-cyano-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolates by isobutyraldehyde and primary amines

摘要

Treatment of N-methylmorpholinium 4-aryl-3-cyano-6-oxo-1,4,5,6- tetrahydropyridine-2-thiolates with an excess of isobutyraldehyde and primary aromatic amines in refluxing ethanol gives the corresponding 7-aryl-3-arylamino-2,2-dimethyl-5-oxo-2,3,6,7-tetrahydro-5H-thiazolo[3,2-a] pyridine-8-carbonitriles in 18-38% yields.