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1.
Trifluoromethylation onto the tetrafluorophthalonitrile and tetrafluoroisophthalonitrile has been carried out using CF3TMS-CuI-KF system, and it was demonstrated that these trifluoromethylation enabled us to successfully construct di- and/or tri-trifluoromethylated benzonitriles via the decyanotrifluoromethylation.  相似文献   
2.
In the presence of a stoichiometric amount of Bu4NF·3H2O, (trifluoromethyl)trimethylsilane reacts with aromatic thiones in both thiophilic and carbophilic ways to deliver, in medium yield, a mixture of (trifluoromethylthio)diarylmethane and 1,1-diaryl-2,2,2-trifluoroethanethiol, the former product being the major one.  相似文献   
3.
In the presence of copper(I) iodide as catalyst, a variety of carbonyl compounds, such as aldehydes, ketones and acid anhydrous, could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields, and a possible mechanism was proposed to explain the roles of catalyst and solvent in the reaction system.  相似文献   
4.
Yoshimitsu Itoh 《Tetrahedron》2006,62(30):7199-7203
It has generally been believed that highly basic Li enolates cannot be applied as substrates for radical trifluoromethylation due to defluorination of the α-CF3 product. However, Li enolates can be in fact employed for radical trifluoromethylation. Moreover, the reaction is extremely fast and the minimum reaction time is only ∼1 s.  相似文献   
5.
Treatment of indolines and N-acylindoles with HF/SbF5/CCl4 yields 6-trifluoro derivatives (indole numbering) whereas indoles and oxindoles give the 5-trifluoro derivatives in good yield.  相似文献   
6.
The easy radical trifluoromethylation of a series of 1,3-dicarbonyl compounds with CF3I is described. The reaction occurs in the presence of a nitrogen base and sodium dithionite in CH3CN-H2O solution. Additionally, we report a new access to ammonium triflinates.  相似文献   
7.
Trifluoromethylation of alkyl radicals is emerging as a powerful tool for C(sp3)–CF3 bond formations. Based on the hypothesis of CF3 group transfer from Cu(II)–CF3 to alkyl radicals, a number of trifluoromethylation reactions have been developed, including trifluoromethylation of alkyl halides, decarboxylative trifluoromethylation of aliphatic carboxylic acids, C(sp3)–H trifluoromethylation, amino‐ and carbo‐trifluoromethylation of alkenes, etc. Challenges in this intriguing field are also discussed.  相似文献   
8.
The first systematic study of heterogeneous fullerene trifluoromethylation using an innovative gradient-temperature gas-solid reactor revealed a significant effect of CF3I pressure on the conversion of C60 and C70 into trifluoromethylated products and on the range of fullerene(CF3)n compositions that were obtained. The design of the reactor allowed us to lower the residence times of fullerene(CF3)n species in the hot zone which resulted in the significant differences in relative isomeric distributions as compared to the earlier methods. For the first time, gram quantities of trifluoromethylated fullerenes were prepared using the new reactor, and the selective synthesis of a single-isomer C60(CF3)2 was developed. The relative reactivity of C70 as a CF3 radical scavenger was found to be much lower than that of C60, especially at an early radical addition stage, which led to the cost-efficient synthesis of C60(CF3)2 from a fullerene extract.  相似文献   
9.
α-Trifluoromethyl alkenes can be used as peptide isosteres, moreover, the pre-installed vinyl group make it possible that transformation to diverse fluorine-containing unities. However, the cross-coupling of benzyl group with α-trifluoromethyl alkenes has yet to be developed. In this report, we describe a general method for the cross-coupling of benzylzinc reagents with 2-bromo-3,3,3-trifluoropropene (BTP) to afford diverse α-trifluoromethylalkene derivatives by using Pd(TFA)2 as catalyst. This method takes advantage of cheap industrial available fluorine building blocks and easily prepared benzylzinc reagents to generate α-trifluoromethylalkene derivatives, which features with mild reaction conditions, wide substrate scope and feasibility of product transformations.  相似文献   
10.
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