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The first example of direct hydrotrifluoromethylthiolation of terminal alkynes in the presence of AgSCF3 and K2S2O8 was established for the synthesis of a variety of vinyl trifluoromethyl thioethers. The anti-Markovnikov and Markovnikov adducts were obtained in moderate to good yields via two different reaction systems. Studies to probe the mechanism of the anti-Markovnikov addition reactions including the radical trapping experiments, kinetic isotope effect experiments, and deuterated experiments for determination of H-sources were conducted.

A mild and efficient method for the preparation of fluorovinyl pyrazolyl ethers and thioethers by the reaction of gem-difluoroalkenes having aryl substituents with pyrazolin-5-ones and pyrazolin-5-thiones, respectively, in the presence of t-BuOK is described.

A practical and convenient approach for the secondary C(sp3)–H arylation of diarylmethanes with various fluoroarenes is described. The reaction proceeds smoothly in the presence of LDA (lithium diisopropylamide) at room temperature and affords triarylmethanes in moderate to high yields.

A direct and efficient approach for the trifluoromethylation and pentafluoroethylation of 1,1-diaryl-2,2-difluoroethenes with TMSCF3 and TMSCF2CF3 in the presence of TBAF is developed.

A novel and efficient one-pot sequential C4-diarylation of pyrazolin-5-ones with diaryliodonium salts in the absence of a metal catalyst was reported. A variety of C4-diarylated pyrazolin-5-one derivatives were obtained in good to high yields under mild conditions.

The reaction fails using gem-difluoroalkenes bearing electron withdrawing groups, aliphatic or hetaryl substituents.

A straightforward and convenient approach for trifluoromethylthiolation of various acyclic and cyclic ketones with PhNHSCF3 is described. The reaction proceeds smoothly in the presence of acetyl chloride at room temperature and affords α-trifluoromethylthiolated ketones in fair to good yields.

The first general route for the efficient synthesis of trisubstituted furan derivatives is developed.

A wide range of monofluoro products are highly efficiently obtained from corresponding gem-difluoroalkenes with high E-selectivity using Red-Al as reductant under mild reaction conditions without any additional base or metal catalyst.

A novel and efficient three-component reaction for the synthesis of fluorovinyl aryl ethers from gem-difluoroalkenes, arylboronic acids and oxygen under metal-free conditions is described.

Direct α-fluorovinylation of 2-phenyl-1,3,4-oxadiazole, benzothiazole and benzoxazole with gem-difluoroalkenes via nucleophilic vinylic substitution reaction (SNV) under the assistance of KHMDS or NaH at room temperature is described.

A novel Kumada–Tamao–Corriu cross-coupling reaction of gem-di- or monofluoroalkenes with Grignard reagents, with or without β-hydrogen atoms, in the presence of a catalytic amount of palladium- or nickel-based catalysts has been developed. The reaction is performed under mild conditions (room temperature or reflux in diethyl ether for 1–2 h) and leads to di-cross- or mono-cross-coupled products in good to high yields.

Langlois reagent (II) is tested under conditions A) in the reactions with 4-substituted acetanilides bearing either electron-donating or electron-withdrawing groups.

A slight excess (1.2 equiv.) of difluoroalkene reacts with various N-heterocycles to afford monosubstituted (E)-configurated products.

A novel Ni-catalyzed cross-coupling of fluoroarenes is developed using alkyl zinc reagents in the presence of sodium.

A novel and mild method for copper-mediated trifluoromethylation of 5-iodotriazole using (trifluoromethyl)trimethylsilane (Me 3 SiCF 3 ) as trifluoromethylating reagent with the assistance of Ag 2 CO 3 was developed.

A novel Cu-catalyzed trifluoromethylation of phthalic and 1,8-naphthoic anhydrides is reported using TmsCF3 as nucleophilic trifluoromethylation reagent.

A novel, inexpensive, and efficient palladium-, copper-, ligand-, and amine-free Sonogashira-type cross-coupling reaction of terminal alkynes with unreactive aryl fluorides in the presence of sodium, sodium methoxide, and calcium hydroxide under the assistance of a Grignard reagent was developed. A plausible mechanism was also suggested.

This method works in absence of a metal catalyst and is suitable for 2-(2-fluorophenyl)pyridine substrates.

A series of 1-aryl-5-trifluoromethyl (or difluoromethyl)–1,4,5-trisubstituted 1,2,3-triazoles were synthesized in high yield by a novel one-pot three-component reaction of arylboronic acids, sodium azide, and active methylene ketones, such as ethyl 4,4-difluoroacetoacetate or ethyl 4,4,4-trifluoroacetoacetate in the presence of Cu(OAc)2 and piperidine using a DMSO/H2O (10/1) mixture as solvent.

A highly efficient and practical approach to the hydrodefluorination of C F bond in fluoroarenes in the presence of 5 mol% NiCl 2 (PCy 3 ) 2 with lithium tri- t -butoxyaluminium hydride (LiAl(O- t -Bu) 3 H) under mild conditions has been developed.

This method uses mild reaction conditions to give the 1,2,3-triazoles (III) in good yields.

Polyfluoro-substituted unsymmetrical biaryl ethers (III) are synthesized via a novel Ni-catalyzed cross-coupling reaction of polyfluoroarenes (I) with arylboronic acids (II) and oxygen.

Desulfuration of amides (IV), obtained by Passerini reaction of phenylsulfanyl-protected isonitrile (I), proceeds efficiently via the corresponding sulfones (V).

Both aromatic C—F bonds and benzylic C—F bonds are converted to C—H bonds by use of the title equimolar catalyst mixture.

Seventeen novel gem-difluoromethylene-containing 1,2,3-triazoles were synthesized by the click reaction of ethyl 2-azido-2,2-difluoroacetate and terminal alkynes in the presence of 10 mol% CuI.

The difluoromethyl-containing Biginelli dihydropyrimidinone derivatives were synthesized by a one-pot cyclocondensation of ethyl 4,4-difluoroacetoacetate, urea, and a variety of aldehydes in the presence of 5 mol% ytterbium perfluorooctanoate [Yb(PFO) 3 ] under solvent and dehydrating agent free conditions. The comparison of reaction conditions and products was made among the different 1,3-dicarbonyl substrates (ethyl acetoacetate, ethyl 4,4-difluoroacetoacetate and ethyl 4,4,4-trifluoroacetoacetate) for the Biginelli reaction.

Fourteen difluoromethyl-containing 1,4-disubstituted 1,2,3-triazoles were synthesized via a novel copper-catalyzed click-multicomponent reaction of 2,2-difluoro-2-phenylsulfanylethanol, sodium azide and terminal alkynes in the presence of N- (p-toluenesulfonyl)imidazole, tetrabutylammonium iodide and triethylamine, followed by reductive cleavage of the phenylsulfanyl group using tributyltin hydride and azobisisobutyronitrile.

An unexpected hydrodefluorination of unactivated aliphatic C–F bonds of CF 2 derivatives with LiAlH 4 at room temperature without any added metal catalyst was reported. Deuterium-labeling experiments suggested that the hydrogens introduced into the products originated from LiAlH 4 .

Hantzsch reaction of ethyl trifluoroacetate at high temperature affords the synthetically and pharmaceutically important polysubstituted pyridines (III) as single products.

A convenient one-pot synthesis of fully substituted pyrazoles via three-component condensations of phenylhydrazine, aldehydes, and 1,3-dicarbonyl compounds using ytterbium perfluorooctanoate [Yb(PFO) 3 ] as catalyst under solvent-free conditions is described. The reusable catalyst can be easily prepared and was efficient for the reaction. A possible mechanism is suggested.

A facile one-step method has been developed for the synthesis of N-protected α-amino aldehyde acetals in moderate to good yields by three-component reaction of fluoroalkanesulfonyl azides, vinyl ethers and alcohol at 0 °C within 10 min. This practical synthetic method provides a convenient and expeditious access to N-per(poly)fluoroalkanesulfonyl α-amino aldehyde acetals.

In the presence of anhydrous potassium carbonate as base, triethylbenzylammonium chloride as phase transfer catalyst, and dimethylformamide as solvent, 4-nitrophenylsulfonylacetate was treated with alkyl acrylate at 70°C to afford the unexpected 3-aryl-1,3,5-pentanetricarboxylic acid trialkylesters via a tandem addition-rearrangement-addition reaction. A possible mechanism was suggested.

Eight 2-(5-(trifluoromethyl)pyridyloxymethyl)-1,3,4-oxadiazoles have been designed and synthesized by four-step synthetic route. The structures of all new compounds were confirmed by 1 H NMR, mass and HR mass spectroscopy. The preliminary bioassay tests show that some compounds, especially those having fluorine on the benzene ring ( II 4 and II 5 ), exhibited a significant insecticidal activity on armyworm, Leucania separata Walker , at 500 mg l −1 .

A novel and simple protocol: the direct amination of 4,5-dichloropyridazinones can be carried out in hydrazine hydrate under mild conditions. 4-Chloro-5-hydrazinopyridazin-3-ones serves as a key intermediate in this reduction.