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One-Pot Synthesis of Novel α,β-Dichloro-β-trifluoromethylated Enones and TheirApplication to the Synthesis of Trifluoromethylated Heterocycles. -Treatment of Weinreb benzamides (II) with trifluoropropynyllithium (I) and subsequent quenching with trifluoromethanesulfonyl chloride afford the α,β-dichlorinated enones (III) together with the monochlorinated derivatives (IV). The formation of enones (III) proceeds likely via a chloroallenyl amine intermediate. Cyclization reactions between enone (IIIa) and amidines (V) or hydrazines (IX) are successful to provide the trifluoromethylated chloropyrimidines (VI) and chloropyrazoles (X). The functionality of the heterocyclic ring system (VI) is utilized by microwave-assisted coupling reactions of (VI) with allyl-and phenylstannanes (VII). -(JEON, S. L.; KIM, J. K.; SON, J. B.; KIM, B. T.; JEONG*, I. H.; J. Fluorine Chem. 128 (2007) 2, 153-157; Dep. Chem., Yonsei Univ., Wonju 220-710, S. Korea; Eng.) -H. Hoennerscheid

Halogen compounds Q 0090Reactions of Novel Trifluoromethyl Propargylic Carbocation with Carbon Nucleophiles. -A propargylic carbocation, generated from the reaction of trimethylsilyl ether (I) with TmsOTf, is coupled with a variety of carbon nucleophiles such as arenes, Grignard reagents and allyltrimethylsilane. -(JEON, S. L.; KIM, J. K.; SON, J. B.; KIM, B. T.; JEONG*, I. H.; Tetrahedron Lett. 47 (2006) 51, 9107-9111; Dep. Chem., Yonsei Univ., Wonju 220-710, S. Korea; Eng.) -Mais 14-078