MANNICH REACTION IN THE SYNTHESIS OF N,S-CONTAINING HETEROCYCLES. 14. UNEXPECTED FORMATION OF THIAZOLO[3,2-<i>a</i>]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
DOI:
https://doi.org/10.1007/1224Keywords:
isobutyraldehyde, N-methylmorpholinium 3-cyano-1, 4, 5, 6-tetrahydropyridine-2-thiolates, thiazolo[3, 2-a]pyridines, aminoalkylation, Mannich reaction, three-component condensationAbstract
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.
Authors: V. V. Dotsenko and S. G. Krivokolysko.
English Translation in Chemistry of Heterocyclic Compounds, 2012, 48 (4), pp 672-676