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The reaction of hexafluoropropene trimers with Ruppert-Prakash (CF 3 SiMe 3 ) reagent gave highly congested perfluoroolefins such as the mono-trifluoromethylation products F -2,4-dimethyl-3-isopropyl-2-pentene ( P1 ) and E - and Z -forms of F -4,4-dimethyl-3-isopropyl-2-pentene ( 2 E and 2 Z ), and the bis-trifluoromethylation product F -2,4,4-trimethyl-3-isopropyl-2-pentene ( 3 ). The E -form of 2 was also comprised of two rotamers. Various aprotic polar solvents were surveyed for this reaction, and it was found that the aprotic solvent DMI has a unique solvent effect to selectively give the mono-trifluoromethylated perfluoroolefin P1 , a precursor for the persistent perfluoroalkyl radical F -3-isopropyl-2,4-dimethyl-3-pentyl, in very high yield. [ABSTRACT FROM AUTHOR]

Reported herein is the one-pot synthesis of trifluoromethylated amines at room temperature using the bench-stable (Me4N)SCF3 reagent and AgF. The method is rapid, operationally simple and highly selective. It proceeds via a formal umpolung reaction of the SCF3 with the amine, giving quantitative formation of thiocarbamoyl fluoride intermediates within minutes that can readily be transformed to N-CF3. The mildness and high functional group tolerance render the method highly attractive for the late-stage introduction of trifluoromethyl groups on amines, as demonstrated herein for a range of pharmaceutically relevant drug molecules. [ABSTRACT FROM AUTHOR]

The trifluoromethylation of enamines of ethyl 3-oxocarboxylates catalyzed by Fenton reagent with CF 3 I was investigated. Trifluoromethylation followed by acid hydrolysis provided 3-oxo-2-(trifluoromethyl)carboxylates in 64–94% yields, which were greater than those obtained by the trifluoromethylation of 3-oxocarboxylates as reported previously. Enamines trifluoromethylated at the 2-position were isolated as intermediates. Hydrolysis and successive decarboxylation of the obtained 3-oxo-2-(trifluoromethyl)carboxylates under acidic conditions provided (2,2,2-trifluoroethyl)ketones in satisfactory yields. [ABSTRACT FROM AUTHOR]

A range of benzotrifluorides are conveniently accessible in high yields from widely available (hetero)aromatic amines and the inexpensive trifluoromethylating agent TMSCF3 through a copper-mediated Sandmeyer trifluoromethylation reaction. Two practical procedures are presented. In the first, the diazonium salts are preformed in an extra reaction step, in the second approach the diazotization and the trifluoromethylation are combined into a one-pot procedure. [ABSTRACT FROM AUTHOR]

The trifluoromethyl group has unique functional properties and is widely used not only in organic chemistry, but also in pharmaceutical and agrochemical science. Here we describe trifluoromethylation reactions of indoles and alkenes using Togni's reagent. These reactions provide useful trifluoromethylated organic compounds, including heterocycles, with high efficiency. [ABSTRACT FROM AUTHOR]

Being economic with fluorine: The direct synthesis of CuCF3 from a cuprate reagent and trifluoromethyl ketones, as one of the most economical and efficient trifluoromethyl sources, was accomplished. The advantages of this method are all of reagents employed are low‐cost, operation is simple, and the yield of CuCF3 is virtually quantitative (see scheme). Furthermore, three types of trifluoromethylations smoothly proceeded to provide the corresponding products in high yields. [ABSTRACT FROM AUTHOR]

Metal‐free: The first metal‐free aryltrifluoromethylation of activated alkenes has been developed. With this method, trifluoromethylated isoquinolinediones, spirobicycles, oxindoles, and α‐aryl‐β‐trifluoromethylamides were obtained with high control of the regioselectivity. [ABSTRACT FROM AUTHOR]

The article presents a study which examines a radical trifluoromethylation of olefins through applying the Langlois reagent. It notes that unactivated olefins have been used as the starting materials. It states that using an olefin as the synthetic precursor instead of a preformed substrate makes the method advantageous. It mentions that mild reaction conditions, wide functional-group tolerance, and the use of an inexpensive trifluoromethylating agent are the main features of the reaction.

Abstract: In situ monitoring of the trifluoromethylation of caffeine using Zn(SO2CF3)2 provides mechanistic insight into this important reaction. The concentration dependences of each of the reagents are probed, along with the effect of various additives. The kinetic profile is characterized by a rapid initial regime followed by a period of slower rate. Increasing the concentration of the Zn reagent extends the initial rapid period to higher conversions. Neither the caffeine concentration nor the concentration of the oxidant has a strong effect on the reaction rate. A multiple aliquot method is introduced to help deconvolute factors associated with each rate regime. [Copyright &y& Elsevier]