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β-Fluorovinamidinium salt ( 1 ) reacted cleanly with a variety of Grignard reagents in tetrahydrofuran at room temperature, followed by acid workup, to produce the corresponding (Z)-α-fluoro-α,β-unsaturated aldehydes ( 3 ) in good to excellent yields.

β-Fluoro vinamidinium salt ( 1 ) reacted with 1.1 equiv. of methylene compounds activated with carbonyl or cyano groups in the presence of lithium diisopropylamide or sodium hydride and triethylamine in tetrahydrofuran at room temperature to give monofluorinated multifunctional dienaminones ( 3 ) and dienaminonitriles ( 5 ) in moderate to good yields. The reactions of 1 with 2.2 equiv. of enolates derived from β-keto esters at 80 °C gave the cyclization products, fluorinated isophthalates ( 6 ) in good yields, while a similar reaction with 2.2 equiv. of cyanoacetate and malononitrile produced the non-cyclic 1, 3-dienecarbonitriles ( 7 ) in excellent yields.

β-Trifluoromethylated vinamidinium salt (1) was prepared in high yield by the reaction between 3,3,3-trifluoropropanoic acid and phosphorus oxychloride in N,N-dimethylformamide at 70 °C for 1 h. This salt 1 reacted readily with bifunctional nitrogen nucleophiles, such as amidine and hydrazine derivatives, in acetonitrile or dimethyl sulfoxide to furnish the corresponding trifluoromethylated azaheterocycles in good yields.

β-Fluorovinamidinium salt (2), readily prepared fromN-(2, 3, 3-trifluoro-1-propenyl)trimethyl-ammonium iodide (1) and diethylamine, reacted with bifunctional hetero nucleophiles such as amidine and guanidine hydrochlorides in the presence of a base to afford regiospecifically monofluorinated pyrimidines4 in good yields. The one-pot procedure starting from1 was applicable for synthesizing heterocyclic compounds4 in almost comparable yields.