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A novel method for the conversion of vinyl triflates into α-trifluoromethylated ketones in the absence of external trifluoromethyl sources is described. This process accomplishes an efficient migration of the trifluoromethyl group of the triflate to the α-position in the ketone through a radical process. The reaction proceeds by the addition of a trifluoromethyl radical to the vinyl triflate and subsequent fragmentation of the trifluoromethane sulfonyl radical. Based on this reaction, a one-pot two-step procedure for the trifluoromethylation of ketones was developed. The method presented herein also allows the transfer of perfluoroalkyl groups from vinyl perfluoroalkanesulfonates, which are readily accessible from alkynes and perfluoroalkanesulfonic acids. [ABSTRACT FROM AUTHOR]

An improved procedure was developed for the synthesis of 3,3,3-trifluoro-1-nitropropene, and a new representative of gem-bromonitroalkenes, 1-bromo-3,3,3-trifluoro-1-nitropropene, was synthesized therefrom. Its reaction with phenyl azide gave a mixture of two regioisomeric 1,2,3-triazoles, from which pure 5-nitro-1-phenyl-4-(trifluoromethyl)-1 H-1,2,3-triazole was isolated. [ABSTRACT FROM AUTHOR]

A method is proposed for the synthesis of 3-nitro-2-phenyl-2-(trifluoromethyl)-2 H-chromenes by tandem condensation of salicylic aldehydes with ( E)-3,3,3-trifluoro-1-nitro-2-phenylprop-1-ene in the presence of triethylamine. The example of 3-nitro-2-phenyl-2-(trifluoromethyl)-2 H-chromene was used to demonstrate conjugated addition reactions with enamines, nitromethane, and aniline, which are characteristic for this class of compounds. The structure of the obtained products was confirmed by X-ray structural analysis. [ABSTRACT FROM AUTHOR]

Efficient preparation of synthetically important CF3-containing α,β-unsaturated esters is described using an NHC-catalyzed multicomponent reaction. This approach combines sequential NHC-mediated HOMO and LUMO activation to produce a C-C bond and C-O bond in a one-pot operation. [ABSTRACT FROM AUTHOR]

An efficient, scalable and operationally simple one-pot, 2-step strategy for the nucleophilic formylation of trifluoromethyl ketones is presented. The key step is an unprecedented diaza-carbonyl-ene reaction of formaldehyde tert-butyl hydrazone and trifluoromethyl ketones under solvent-free conditions. This reaction proved to be very fast, clean and high-yielding, affording densely functionalised α-hydroxy α-trifluoromethyl diazenes. The ensuing diazene-to-aldehyde transformation, avoiding protection/deprotection reactions and chromatographic purifications, and subsequent derivatizations in a one-pot fashion provide a direct entry to a variety of useful trifluoromethylated building blocks. [ABSTRACT FROM AUTHOR]

A highly enantioselective Diels–Alder reaction of 4,4,4-trifluorocrotonaldehyde and dienes was performed with a diarylprolinol silyl ether catalyst. The reaction with cyclopentadiene, 1,3-cyclohexadiene, and 2-substituted 1,3-butadienes yielded the corresponding cycloadducts bearing a trifluoromethylated chiral carbon center with up to 97% ee, whereas the reaction with furan yielded the corresponding Friedel–Crafts adduct with high enantioselectivity. [ABSTRACT FROM AUTHOR]

This paper describes an efficient approach for the synthesis of 2-(trifluoromethyl)-1,2,3,4,7,8-hexahydroquinolin-5(6 H)-one derivatives via a one-pot four-component reaction of aromatic aldehyde, 5,5-dimethylcyclohexane-1,3-dione, 4,4,4-trifluoro-1-(thien-2-yl)butane-1,3-dione, and NH4OAc with excellent yields at room temperature. In this synthesis, the trifluoromethyl was efficiently introduced in hexahydroquinoline structure, and they may be valuable the drug candidates. This approach also offered several other advantages, such as catalyst-free, mild conditions, and simple experimental operation. [ABSTRACT FROM AUTHOR]

Unlike the hydrocarbon analogs, this first report of enolboration–aldolization of 3,3,3-trifluoropropanoic acid provides essentially pure anti -diastereomers of α-trifluoromethyl-β-hydroxy carboxylic acids in 77–90% yields. [ABSTRACT FROM AUTHOR]

The title reaction proceeds with acetylenic triflones and isocyanides under mild conditions using copper as a catalyst. This transformation provides an efficient access to (E)-N-alkyl trifluoromethyl alkynyl ketoimines, which are useful building blocks for the synthesis of CF3-containing N-heterocycles, propargylamines, etc. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of ethyl 4-aryl-6-(trifluoromethyl)-2-oxo-2H-pyran-3-carboxylates, prepared from 4,4,4-trifluorobutane-1,3-diones, PCl5 and sodium diethyl malonate, with sulfuric acid afforded the intramolecular Friedel–Crafts acylation products, 3-(trifluoromethyl)indeno[2,1-c]pyran-1,9-diones, from which 2-(trifluoromethyl)-6H-pyrano[3,4-c]quinoline-4,5-diones were obtained via the Schmidt reaction in moderate yields. The latter reacted with sodium azide to give 2-oxo-4-(5-trifluoromethyl-1,2,3-triazol-4-yl)-1,2-dihydroquinoline-3-carboxylic acids in good yields. [Copyright &y& Elsevier]

A cascade approach to 1-(trifluoromethyl)-4-fluoro-1,2-dihydroisoquinolines and 4,4-difluorotetrahydroisoquinolines has been developed. The procedure involves a silver-catalyzed intramolecular aminofluorination of alkyne. This one-pot reaction provides an efficient way to synthesize various fluorinated isoquinolines. [ABSTRACT FROM AUTHOR]

A two-step process for the synthesis of trifluoromethyl-substituted cyclopropanes is described. Halothane, an anesthetic agent, is added to olefins in a ruthenium-catalyzed Kharasch reaction. The resulting 1,3-dihalides are converted into cyclopropanes by dehalogenation with magnesium. This procedure represents an alternative to metal-catalyzed cyclopropanations involving trifluoromethyl diazomethane. [ABSTRACT FROM AUTHOR]

4,4,4-Trifluoro-1-(thiophen-2-yl)butane-1,3-dione was reacted by grinding with cyanothioacetamide and cyanoacetamide under solvent-free conditions at 25 ±C to give pyridine-2(1H)thione/one derivatives in excellent yields. These compounds were further reacted by grinding with different halogenated reagents to give 2-S/O-alkyl pyridine derivatives. The latter compounds were utilized for the synthesis of thieno[2,3- b]pyridine, pyrazolopyridine, pyridothienopyrimidine and pyridothienooxazinone derivatives. [ABSTRACT FROM AUTHOR]