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Abstract: A new protocol has been developed for the synthesis of α-trifluoromethyl ketones via organocatalyzed decarboxylative trifluoromethylation of β-ketoacids with Togni’s reagent. Among various simple amine catalysts, primary amines and secondary amines were identified to be more effective than tertiary amines, with piperazine being the most effective. Mechanistic investigations suggested that the primary or secondary amine-catalyzed reactions proceed mainly through trifluoromethylation of an enamine intermediate, which is more effective than the tertiary amine-catalyzed pathway that involves an enol intermediate. By using piperazine as the optimal organocatalyst, various β-ketoacids, including the sterically hindered α,α-disubstituted ones, were converted into the corresponding α-trifluoromethyl ketones in good yields. This research not only provides a useful strategy for the efficient synthesis of a wide range of α-trifluoromethyl ketones under mild conditions, but also constitutes one of the few studies on decarboxylative alkylation of β-ketoacids, which can intrigue further exploitation on organocatalyzed asymmetric decarboxylative alkylation reactions.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The reaction of the divalent ruthenium complexes [CpFRuCl]n and [CpFRu(MeCN)3]PF6 with substituted pentafulvenes 1,2-(Me2NCH)(CO2Et)C5H3 and 1,3-(Me2NCH)(CO2Et)- C5H3 followed by hydrolysis affords new homoannular disubstituted ruthenocenes {1,2- (CO2Et)(CHO)C5H3}RuCpF and {1,3-(CO2Et)(CHO)C5H3}RuCpF (CpF = C5Me4CF3), re- spectively. [ABSTRACT FROM AUTHOR]

The copper $$\hbox {CF}_{3}$$ or $$\hbox {SCF}_{3}$$ complexes as the fluoride sources for the synthesis of trifluoromethylated or trifluoromethylthiolated compounds are reviewed. Compared with the ordinary fluoride reagents, the addition of reactant species in the reaction systems of copper trifluoromethyl or trifluoromethylthio complexes were less, so the reaction systems are relatively simple and easy to operate. In most cases, the trifluoromethylated or trifluoromethylthiolated products were obtained in moderate to excellent yields. GRAPHICAL ABSTRACT: SYNOPSISThis mini-review highlights recent developments in trifluoromethylation or trifluoromethylthiolation using copper $$\hbox {CF}_{3}$$ or $$\hbox {SCF}_{3}$$ complexes, such as (phen) $$\hbox {CuCF}_{3}$$ , (phen) $$\hbox {Cu}(\hbox {CF}_{3})_{3}$$ , (bpy) $$\hbox {Cu}(\hbox {CF}_{3})_{3}$$ , $$(\hbox {Ph}_{3}\hbox {P})_{3}\hbox {CuCF}_{3}$$ , and (bpy) $$\hbox {CuSCF}_{3}$$ . [ABSTRACT FROM AUTHOR]

Metal complexes display functional interfaces for association with and stimulation of certain enzymes, that are liable to transfer genetic information in DNA for synthesis of specific proteins. Biological activity of five organotin carboxylates based on the ligand, 4-oxo-4-[3-(trifluoromethyl)phenylamino]butanoic acid, such as [BuSnL] ( 1), [PhSnL] ( 2), [MeSnL] ( 3), [BuSnL] ( 4), and [PhSnL] ( 5) have been synthesized and their biological activity as a function of substitution on the ligand was tested. Structure of the complexes was evaluated by elemental analysis, FT-IR and H, and C NMR spectra. FT-IR data and theoretical calculations revieled that the ligand acted as bidentate in complexes 1- 5. NMR data revealed four and six coordinated geometry of tin in solutions. The HOMO-LUMO study indicated thermodynamic stability of the complexes. AFM confirmed catalytic potential of the synthesized complexes. Biological screening showed that, with few exceptions, all the complexes exhibited significant activity against various bacterial and fungal strains. UV-Vis study confirmed that the ligand and its complexes binded to DNA via intercalative interactions. [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]

Considering the increasing importance of fluorinated peptides, the development of efficient and reliable synthetic methods for the incorporation of unnatural fluorinated amino acids into peptides is a current matter of interest. In this study, we report the convenient Boc/benzyl and Cbz/ tert-butyl protection of both enantiomers of the quaternarized amino acid α-trifluoromethylalanine [( R)- and ( S)-α-Tfm-Ala]. Because of the deactivation of the nitrogen atom of this synthetic amino acid by the strong electron withdrawing trifluoromethyl group, the peptide coupling on this position is a challenge. In order to provide a robust synthetic methodology for the incorporation of enantiopure ( R)- and ( S)-α-trifluoromethylalanines into peptides, we report herein the preparation of dipeptides ready to use for solid phase peptide synthesis. The difficult peptide coupling on the nitrogen atom of the α-trifluoromethylalanines was performed in solution phase by means of highly electrophilic amino acid chlorides or mixed anhydrides. The synthetic effectiveness of this fluorinated dipeptide building block strategy is illustrated by the solid phase peptide synthesis (SPPS) of the Ac-Ala-Phe-( R)-α-Tfm-Ala-Ala-NH tetrapeptide. [ABSTRACT FROM AUTHOR]

N-Benzyloxycarbonyl-2,2,2-trifluoroacetimidoyl chloride reacted with pyridin-2-amine derivatives to form substituted 2-trifluoromethyl-4 H-pyrido[1,2- a][1,3,5]triazin-4-ones. [ABSTRACT FROM AUTHOR]

The article reports on the results on the synthesis of trifluoromethyl derivatives of C60, isolation, and molecular structure of two new isomers of C60(CF3)12 and one isomer of C60(CF3)14. It discusses possible reasons of deviations from a regular course of the synthesis when a sublimed mixture of C60-C70 is used. It also considers the most probable ways for the formation of new isomers.