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Reactions of 1,1,1-trifluoro-2-iodoethane with alkylalkenes and silyl enol ethers were performed in the presence of a catalytic amount of fac-Ir(ppy)3 and an excessive amount of Hunig’s base in acetonitrile irradiated by a 24 W fluorescent lamp under nitrogen atmosphere for 48 hours. The visible-light-induced photoredox reactions introduce simultaneously a 2,2,2-trifluoroethyl group and an iodine atom to both sides of the double bond of ordinary alkenes via an atom-transfer radical addition (ATRA). The same reaction with silyl enol ethers generates β-trifluoromethyl ketones, which are typically a challenge to synthesize. The reactions proved to be tolerant of a variety of functionalities.

Herein, we report a convenient methodology for the synthesis of fluorinated 1,4,5-substituted 1,2,3-triazoles. The azide–alkyne cycloaddition reaction of internal alkynes catalyzed by a ruthenium complex efficiently afforded 2,2,2-trifluoroethyl- and (trifluoromethyl)thio-substituted 1,2,3-triazoles. Two types of internal alkyne, 1-aryl-2-(2,2,2-trifluoroethyl)acetylenes and 1-aryl-2-[(trifluoromethyl)thio]acetylenes, were used. This ruthenium-catalyzed azide–alkyne cycloaddition reaction was highly regioselective giving 4-aryl-5-(2,2,2-trifluoroethyl)- or 4-aryl-5-[(trifluoromethyl)thio]-1H-1,2,3-triazoles. Various functionalities were tolerated in the alkyl and aryl azides by this Huisgen 1,3-dipolar cycloaddition. All the triazoles were characterized by 1H, 13C, and 19F NMR, IR, and HRMS (or elemental analysis). Several triazoles were characterized by single-crystal X-ray structural analysis to confirm the regioselectivity of 1,2,3-triazole formation.

The visible-light-induced photoredox difunctionalization reactions of styrenes with 1,1,1-trifluoro-2-iodoethane under an oxygen atmosphere in the presence of water give γ-trifluoromethyl alcohols. In this radical reaction, the oxygen atom in the product originates from molecular oxygen, and water is shown to be important to promote the reaction.

The title reaction provides a novel utilization of ozone-depleting/global-warming HCFCs as a new carbon–carbon cross-coupling model of various terminal alkynes by activating two inert C–Cl bonds successively. This protocol provided trifluoroethylated alkynes efficiently under mild reaction conditions and was compatible with a broad range of functional groups. An example of the synthesis of a terbinafine analogue is shown. Some mechanistic experiments including deuterated reagents and radical/SET inhibitors are described.

The trifluoromethylthiolation of unactivated C—H bonds is proposed to involve a radical process in which potassium persulfate shows key behavior in both the activation of the C—H bond and the oxidation of the silver reagent.

Ten α-trifluoromethyl ketones of type (III) are prepared from aromatic alkenes (I) and Togni′s reagent (II) in a visible light-catalyzed photoredox trifluoromethylation reaction.

A mild method of converting arylamines into perfluoroalkylated arenes is described. Relatively stable RFCu(CH3CN) complexes are used as perfluoroalkylating agents, which react smoothly with arenediazonium salts to produce various perfluoroalkylarenes in good yields. Based on the results of clock trapping experiments with diallyl ether, a radical process might be involved in the reaction.

Oxidative coupling of benzylamines to imines by molecular oxygen is efficiently realized in the presence of very low catalyst loadings of Co(II) β-tetrakis(trifluoromethyl)-meso-tetraphenylporphyrin. Due to the effect of four β-CF3 groups, the catalyst shows good selectivity and very high turnover number. The reaction is easily scaled up and may provide a convenient way to prepare many imines in large scale.

Tetrafluoroethane β-sultone (TFES) has hundreds of useful fluorinating derivatives as reagents. The reactions of TFES with nucleophiles provide a variety of interesting fluoroalkylsulfonic acids and their derivatives, as well as ω-halo-perfluoropentanesulfonyl fluorides. Fluorosulfonyldifluoroacetic acid derivatives such as FSO2CF2COOH, FSO2CF2COOMe, FSO2CF2COOTMS, HCF2SO2R (R = F, OH, OCF2H, OC6H5), ICF2SO2F, and RCF2OCF2CF2SO2F (R = CF2I, CO2Me, CO2Na) are versatile difluoromethylation and/or trifluoromethylation reagents. FSO2CF2COOH, FSO2CF2COOMe, FSO2CF2COOTMS, HCF2SO2R, and ICF2SO2F can effectively incorporate a CF2 group into O H, N H, S H, C C, and C C bonds. HCF2SO2R (R = OH, OCF2H, OC6F5) and FSO2CF2CO2H generate difluorocarbene under acidic conditions, which significantly expanded the scope of the carbene-based difluoromethylation reactions. FSO2CF2CO2Me, FSO2CF2I, and RCF2OCF2CF2SO2F (R = CF2I, CO2Me, CO2Na) are powerful trifluoromethylation reagents, with FSO2CF2CO2Me being world-renowned and widely used in the design of drug candidates and synthesis of novel functional materials. FSO2CF2CO2Me, FSO2CF2I, and RCF2OCF2CF2SO2F are generally produced by nucleophilic substitution, thermal decomposition, or single-electron transfer mechanism in trifluoromethylation reactions under mild conditions. FSO2CF2CF2OCF2CO2Me can successfully trifluoromethylate unactivated aryl chlorides with CuI, and FSO2CF2CF2OCF2CO2K/CuI can smoothly transform aryl halides at very low temperature. For more than half a century's development, the chemistry of TFES and its derivatives has been extensively studied. This review recounts the recent progress of TFES and reports on TFES-derived difluoromethylation and trifluoromethylation reagents. The syntheses and reactivities of these interesting reagents, as well as their applications in medicinal chemistry and materials science, are briefly summarized.

Significant synthetic challenges remain for the asymmetric synthesis of tertiary α-fluoro ketones, which are potentially useful molecules for the development of drugs, agrochemicals, and functional materials. Herein, we describe the development of a method for the catalytic enantioselective synthesis of tertiary α-fluoro ketones via the Tsuji–Trost reaction of racemic acyclic α-fluorinated ketones. Enantioenriched acyclic α-cabonyl tertiary fluorides can be produced with the aid of a palladium/phosphinooxazoline catalyst.

Subporphyrin (I) shows a red-shifted UV/Vis absorption band that arises from macrocycle nonplanar distortion induced by the trifluoromethyl groups.

A method has been developed for the synthesis of α-trifluoromethyl ketones via the Cu-catalyzed trifluoromethylation of silyl enol ethers with an electrophilic trifluoromethylating agent, which produces a trifluoromethyl radical.

A facile and efficient synthesis of thienopyrimidine derivatives (IV) via reaction of carbodiimide derived from iminophosphorane (I) with secondary amines is developed using potassium carbonate as inorganic base catalyst.

The title reaction proceeds in the presence of a phosphine organocatalyst in an aerobic atmosphere.

X(CF2CF2)(5)OCF2CF2SO2F (X=I, Br, Cl; n=1, 2, 3, 4) are widely used fluoroalkylation reagents, which can incorporate 'heavy' fluorous tags into organic compounds. X(CF2CF2)OCF2CF2SO2F have both sulfonyl and halo groups. They behave as bi-functional fluoro

A new fluorinated anionic surfactant Cl(CF2)6O(CF2)2SO3N(C2H5)4 was prepared and characterized. The application of the fluorosurfactant allowed the fluoroalkylation to occur in the water without adding organic solvent. The addition of perfluoroalkyl iodides with olefins and alkynes under the initiation of Na2S2O4 in water in the presence of the fluorosurfactant gave the corresponding adducts in good to excellent yields. The fluorosurfactant was suitable for a radical addition process.

Compounds (III) and (V) containing an all-carbon quaternary center are synthesized by allylic C—H alkylation of allylarenes (I) with esters (II) and (IV).

A key intermediate, difluoromethylene phosphobetaine, in the Wittig reaction of ClCF2CO2Na–Ph3P with aldehydes was synthesized and characterized, which confirmed the reaction mechanism. The decarboxylation of this stable intermediate was a convenient approach for Wittig difluroolefination. Its reactivity could be adjusted by the modification of the substituent on the phosphorus.

Tsuji-Trost reaction (Pd-catalyzed allylic alkylation) of CF3-containing esters with three electron-withdrawing groups is reported. The reactions with methyl bis(trifluoromethyl) acetate and dimethyl ( trifluoromethyl) malonate were carried out with low-l

The reactions with various electron-deficient olefins proceed under neutral conditions to form the biologically important target compounds bearing a quarternary carbon center.

Starting from the naturally occurring degraded limonoid fraxinellone (I) a series of new hydrazones (IV) and (VI) are prepared and tested for their insecticidal activity against the pre-third-instar larvae of Mythimma separata Walker.

A variety of quaternary α-aryl-α-fluoroketones are easily prepared by direct Pd-catalyzed α-arylation of both open-chain and cyclic α-fluoroketones using P(o-tolyl)3 or RuPhos as ligand.

Nitroaldol reaction of fluorinated nitro compounds with various aldehydes results in the diastereoselective formation of anti-β-fluoro-β-nitroalcohols, in general.

The Mukaiyama aldol reaction of fluorinated silyl enolate (I) with various aldehydes affords α-fluoro-β-hydroxyphenones with up to 86% d.e.

Due to the bulky C-1 substituent and in the presence of boron trifluoride etherate, O-acylation of 2-chloropodophyllotoxin (I) proceeds stereoselectively with retention of the configuration at C-9.

The introduction of electron-donating or -withdrawing groups into different moieties of title compounds (III), which tunes the acidity of the H-bond donor moiety or the basicity of the H-bond acceptor, has a positive effect on the selectivity and sensitivity of such “proton-transfer” chemosensors for anions.

Treatment of difluorodiiodomethane with phenoxides (ArO−) in DMF at room temperature gives ArOCF2I in 7–15%, the carbonates (ArOCO2Ar) being the major products, while with thiophenoxides affords difluoromethylene derivatives (ArSCF2I, ArSCF2SAr, and ArSCF2H) also in low yields.

A review of difluoromethylene compounds as precursors to carbonyl compounds. Many ketones, carboxylic acids, esters, amides and carbonates, especially trifluoroalanine dipeptides, can be easily achieved due to the reactivity of difluoromethylene compounds or generated through the reactive difluoromethylene intermediates.

Difluorodiiodomethane is prepared in 60% yield by the reaction of difluoro(fluorosulfonyl)acetyl fluoride with I2/KI in the presence of a catalytic amount of SiO2 in acetonitrile at 60-65 °C.