Facile and regioselective synthesis of new fluorinated [1,2,4]-triazolo[4,3-a]pyrimidin-7(1H)-one derivatives from fluorinated alkynes

Highly regio- and stereocontrolled preparation of α-(trifluoromethyl)-β-(phenylthio) enamines by the hydroamination of in situ-synthesized 1-(trifluoromethyl)-2-(phenylthio)ethyne

Various nitrogen nucleophiles were easily added to in situ-generated 1-(trifluoromethyl)-2-(phenylthio)ethyne to afford the corresponding trifluoromethyl enamines in good-to-high yields and with high regio- and stereocontrol under very mild conditions.

Simple and Expedient Access to Novel Fluorinated Thiazolo- and Oxazolo[3,2-a]pyrimidin-7-one Derivatives and Their Functionalization via Palladium-Catalyzed Reactions

An efficient, versatile, and one-pot method for the preparation of novel fluorinated thiazolo- and oxazolo[3,2-a]pyrimidin-7-ones is described from 2-aminothiazoles or 2-amino-oxazoles and fluorinated alkynoates. This transformation, performed under transition-metal-free conditions, offers new fluorinated cyclized products with good to excellent yields. Moreover, the functionalization of these N-fused scaffolds via the Suzuki-Miyaura and Sonogashira cross-coupling reactions led to the synthesis of highly diverse thiazolo- and oxazolo[3,2-a]pyrimidin-7-ones.