Regioselective Syntheses of 3-Benzyl-Substituted 7H-Thiazolo[3,2-a]pyrimidine-7-ones through Palladium-Catalyzed Heteroannulation of Acetylenic Compounds

Abstract

An efficient synthesis of 3-benzyl-substituted 7H-thiazolo[3,2-a]pyrimine-7-ones in acetonitrile is accomplished via Pd-and Cucatalyzed reaction of 2-mercaptopropargylpyrimidone with various aryl iodides in the presence of triethylamine as the base.

Synthesis and Growth Stimulant Properties of 2-Acetyl-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidin-5-one Derivatives

“…The cyclization of pyrimidine derivatives may yield several isomers, due to substitution position in pyrimidine cycle in the intermediate product. To achieve regioselectivity, the cyclization reaction was carried out with bromomalononitrile [9] or via S-propargyl derivatives [44,45].…”

“…Their further condensation with substituted acyl chlorides, halocarboxylic acids esters, or dicarbonyl compounds affords thiazolo[3,2a]pyrimidine biheterocyclic systems. In order to accelerate the synthesis of targeted thiazolo[3,2-a]pyrimidines and increase their yield, some authors used MW irradiation [9,14,43] or catalysts [44,45].…”