Aromatic Trifluoromethyl Research Articles

Inhibition of antennal esterases of the egyptian armyworm Spodoptera littoralis by trifluoromethyl ketones

A series of aliphatic and aromatic trifluoromethyl ketones has been tested as inhibitors of the antennal esterases of the Egyptian armyworm Spodoptera littoralis, by evaluation of the extent of hydrolysis of [1- 3H]-( Z,E)-9, 11-tetradecadienyl acetate ( 1), a tritiated analog of the major component of the sex pheromone. The most active compounds with a long chain aliphatic structure were 3-octylthio-1,1,1-trifluoropropan-2-one ( 2) (IC 50 0.55 μM) and 1,1,1-trifluorotetradecan-2-one ( 4) (IC 50 1.16 μM). The aromatic compounds were generally less potent inhbitors than the coressponding aromatic ones, although β-naphthyltrifuloromethyl ketone ( 10) exhibited a remarkable inhibitory activity (IC 50 7.9 μM). Compounds 2, 4 and 10 exhibit a competitive inhibition with K i values of 2.51×10 −5 M, 2.98×10 −5 M and 2.49×10 −4 M, respectively. Some of the trifluoromethyl ketones tested were slow-binding inhibitors and compounds 2 and 10 are described as inhibitors of the antennal esterases of a moth for the first time.

Trifluoromethylation with sodium trifluoromethanesulfinate under oxidative conditions

Trifluoromethyl radicals ·CF 3 can be generated by monoelectronic oxidation (for instance with tertiobutyl hydroperoxide) of sodium trifluoromethanesulfinate (CF 3SO 2Na). This useful and cheap precursor of triflic acid results from bromotrifluoromethane and sulfur dioxide radical-anion (1). Under these conditions, CF 3SO 2Na is able to convert mildly organic disulfides into tri-fluoromethyl thioethers (2) and to trifluoromethylate enol esters. In the latter case, additional catalytic amounts of cupric salts are necessary to oxidize the intermediate radical, in order to prevent the formation of by-products. The reaction can be thus considered as a formal electrophilic trifluoromethylation. Aromatic trifluoromethylation can be also performed with the same system and the ratio between mono and his trifluoromethylated products is dependent upon the presence or absence of catalytic cupric salts. ▪

Reactions of bromotrifluoromethane and related halides: synthesis of trifluoromethyl sulphides from disulphides

The reaction of trifluoromethyl bromide with disulphides in the presence of dithionite or hydroxymethanesulphinate salts in DMF–H2O (DMF = dimethylformamide) medium leads to the formation of aliphatic and aromatic trifluoromethyl sulphides.

ChemInform Abstract: Direct Perfluoroalkylation Including Trifluoromethylation of Aromatics with Perfluoro Carboxylic Acids Mediated by Xenon Difluoride.

AbstractTreatment of the aromatic compounds (I) with the perfluorocarboxylic acids (II) and xenon difluoride results in perfluoroalkylation by intermediate perfluoroalkyl radicals, producing the compounds (III).

Direct perfluoroalkylation including trifluoromethylation of aromatics with perfluoro carboxylic acids mediated by xenon difluoride

Direct perfluoroalkylation including trifluoromethylation of aromatics with perfluoro carboxylic acids mediated by xenon difluoride

ChemInform Abstract: A Facile Synthesis of Aromatic Trifluoromethyl Compounds via Orthothio Esters.

AbstractThe orthothio esters (I) react with the brominating agents (II) or (III) in the presence of HF/Py to produce the trifluoromethyl derivatives (IV).

A facile synthesis of aromatic trifluoromethyl compounds via orthothio esters

Aromatic trifluoromethyl compounds ( 2) are prepared by treatment of aromatic orthothio esters ( 1) with 1,3-dibromo-5,5-dimethylhydantoin (DBH) or N-bromosuccinimide (NBS) followed by HF/pyridine complex. The starting materials ( 1) were readily obtained by literature methodology.

ChemInform Abstract: A NEW METHOD FOR THE TRIFLUOROMETHYLATION OF AROMATICS

Chemischer InformationsdienstVolume 12, Issue 51 Isocyclic Compounds ChemInform Abstract: A NEW METHOD FOR THE TRIFLUOROMETHYLATION OF AROMATICS A. MARHOLD, A. MARHOLDSearch for more papers by this authorE. KLAUKE, E. KLAUKESearch for more papers by this author A. MARHOLD, A. MARHOLDSearch for more papers by this authorE. KLAUKE, E. KLAUKESearch for more papers by this author First published: December 22, 1981 https://doi.org/10.1002/chin.198151171AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume12, Issue51December 22, 1981 RelatedInformation

Synthesis of aromatic trifluoromethyl compounds by ring expansion of cyclodienes

Chlorotrifluoromethyl-1-diazirine was used for a source of chlorotrifluoromethyl carbene. The carbene added to cyclic dienes to give trifluoromethylated six-membered aromatic compounds. Thus, pyrrole gave 3-(trifluoromethyl)pyridine and cyclopentadiene gave benzotrifluoride. In the course of out research to develop a new synthetic method for aromatic trifluoromethyl compounds [1], we planned to use the reaction of chlorotrifluoromethyl carbene (1) with a five-membered cyclic diene. The reaction of pyrrole with dichlorocarbene was reported to give 3-chloropyridine [2]. Therefore, we expected that the similar type of reaction of 1 with a five-membered cyclic diene would provide a new method for the syntheses of aromatic trifluoromethyl compounds. We chose chlorotrifluoromethyl-1-diazirine (2) [3] as the precursor of 1. First, we examined the reaction of 2 with cyclohexene to learn the reactivity of 1. Heating the solution of 2 in cyclohexene at 120° for 3 h gave two adducts (3 and 4). Both products were separated by the preparative g.l.c. using a DEGS column of 7 m at 60°C. 3: 36%; m/e 198 (M +); 1H-NMR δ(CDCl 3) 0.88−2.60 (m); 19F-NMR δ [4] 10.2. 4: 10% m/e 198; 1H-NMR δ(CDCl 3) 0.80−2.60; 19F-NMR δ −1.2. Compound 3 reacted with silver trifluoroacetate to give 2-(trifluoromethyl)cyclohepten-3-yl trifluoroacetate, while 4 did not. This result established the Stereochemistry of both products as shown in Chart 1. This reaction showed that 2 was a good precursor of 1 and that 1 had a high reactivity to a double bond. To utilized this reaction for the synthesis of an aromatic trifluoromethyl compound, thermolysis of 2 with five-membered cyclic dienes was investigated. A solution of 2 (230 mg) in pyrrole (500 mg) was sealed in a Pyrex tube under vacuum and heated at 120°C for 2 h. The reaction mixture was purified by a trap-to-trap distillation. Analysis of the distillate by g.l.c. showed that 3-(trifluoromethyl)pyridine (5) was obtained in 35% yield based on 2. The g.l.c-mass spectrum and 19F-NMR of 5 were identical with those of the authentic sample [5]. Similar thermolysis and work-up of a solution of 2 (160 mg) in cyclopentadiene (550 mg) at 140°C for 3 h gave benzotrifluoride in 23% yield. All the results are summarized in Chart 1. The characteristic point of this procedure is that a trifluoromethyl group was introduced to a five membered ring with one carbon atom under ring expansion. Yields shown above were not optimized and this method can be used for synthesis of some aromatic trifluoromethyl compounds, which are difficult to synthesize by the usual methods.

A new method for the trifluoromethylation of aromatics

A new method is discribed for introducing a CF 3-group, by a single-step synthesis, into aromatic compounds. This trifluoromethylation is done by means of a mixture consisting of HF/CCL 4 and the aromatic compound. The reaction is thought to be of a Friedel-Crafts type and limited to aromatics which are not substituted by electron withdrawing groups.

Reactions of aromatic trifluoromethyl compounds with nucleophilic reagents

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactions of aromatic trifluoromethyl compounds with nucleophilic reagentsYoshiro Kobayashi and Itsumaro KumadakiCite this: Acc. Chem. Res. 1978, 11, 5, 197–204Publication Date (Print):May 1, 1978Publication History Published online1 May 2002Published inissue 1 May 1978https://doi.org/10.1021/ar50125a004RIGHTS & PERMISSIONSArticle Views812Altmetric-Citations65LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (853 KB) Get e-Alerts Get e-Alerts

The characteristic infrared absorption frequencies of aromatic trifluoromethyl compounds

The characteristic infrared absorption frequencies of aromatic trifluoromethyl compounds