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Although CF3SO2Cl is an efficient chlorotrifluoromethylation reagent, an expensive transition metal complex usually has to be used. We found that CuCl2-catalyzed chlorotrifluoromethylation of alkenes with CF3SO2Cl occurred smoothly under mild conditions. A wide substrate scope and good functional group compatibility were observed.

As trifluoromethylthiolation has received increasing attention recently, many CF3S-reagents and trifluoromethylthiolation methods have been developed. Herein we describe trifluoromethylthiolation of alkyl halides by using Ph3P+CF2CO2− as a fluoride and difluorocarbene source. Difluorocarbene is a versatile intermediate, but its side reactions are usually ignored and the by-products would therefore be discarded. In this work, a side reaction of difluorocarbene, the generation of a fluoride anion from difluorocarbene, was developed into a synthetic tool. Although the trifluoromethylthiolation reaction involved multi-sequential steps, the cleavage of C–F bond, the formation of CF2=S bond, F-C(S)F2 bond, and C-SCF3 bond, the conversion proceeded fast and was completed within 10 min.

The preparation conditions and purification reaction mechanism for H2–HF treatment of molten FLiNaK salt were investigated. The optimal process conditions for preparation of high-purity molten FLiNaK salt were obtained. They are purification temperature of 650 °C, liquid height of 0.9 m, purification time of 48 h, flow ratio of H2/HF = 10, flow volume magnitude of 800 mL/min, and reaction pressure of 0 MPa. The oxygen content of the prepared molten salt was around 80 ppm, corrosion impurity elements (Cr, Fe, and Ni) were less than 20 ppm, and the S and P contents were below 5 ppm. The quality of FLiNaK molten salt prepared by this hydrofluorination process is better than that obtained by adding NH4HF2 as a fluorinating reagent.

A fluorinated substituent on the positive phosphorus in phosphonium salt [Ph3P+CF(Me)CO2Et Br−] was found to be able to act as a nucleophile to realize monofluoroalkylation of aldehydes, ketones and imines.

The base-free O- difluoromethylation of 1,3-diones with difluorocarbene generated from difluoromethylene phosphobetaine (Ph 3 P + CF 2 CO 2 − ) is described. The convenient reactions proceeded smoothly to give difluoromethyl enol ethers in moderate to good yields.

The high demand for the biologically active CF2H-molecules has stimulated significant efforts to develop efficient methods for the installation of CF2H functionality. We found that phenylsulfonyl difluoroacetate salt (PhSO2CF2CO2− K+) could directly undergo decarboxylation under warming conditions to produce active anion (PhSO2CF2−) without the need of any base or additive, thus allowing for the subsequent nucleophilic (phenylsulfonyl)difluoromethylation of aldehydes or imines to give PhSO2CF2-alcohols or -amines, respectively. Interestingly, the removal of PhSO2 group was achieved simply by elevating the reaction temperature for the conversion of aldehydes to afford CF2H-ketones.

Affinity, which is the essential attribute of metal ions, is very important to their physical and chemical properties. To make quantitative description and deep understanding on the affinity, fourteen metal ions were considered, and two representative ligands (H2O and NH3) were selected. Five types of energy of five models have been calculated using the density functional theory. Then, the results have been applied to quantify the affinity and describe its evolution in the ligand exchange process. Three aspects, energy decomposition analysis, natural bond orbital analysis, and information-theoretic approach in density functional reactivity theory, have been considered to understand the affinity.

The installation of a HCF2 group is a research area that has received increasing attention, and deoxydifluorination of aldehydes have served as an attractive protocol due to the wide availability of aldehydes. Herein we describe a Ph2S/Selectfluor-promoted deoxydifluorination of aldehydes under mild conditions. Compared with previous deoxydifluorination methods, which usually use hazardous reagents such as SF4, DAST and Deoxo-Fluor, this protocol is quite attractive because of the safe and convenient operations, and the use of easily available reagents.

The development of efficient protocols for the synthesis of gem-difluoroolefins has received increasing attention. Given the ubiquity of hydroxyl group in biologically active molecules and synthetic intermediates, we developed a one-step protocol for the conversions of alcohols into gem-difluoroolefins. The reactions of alcohols with Ph3P+CF2CO2−/Burgess reagent in DMSO occurred smoothly to afford the final products in moderate to high yields. DMSO is not only necessary for the oxidation process, but also important for the stabilization of phosphonium ylide by trapping difluorocarbene.

(NH 4 ) 2 BeF 4 was synthesized and purified by recrystallization to remove sulfate ions before being used as the main raw material to prepare Li 2 BeF 4 molten salt. (NH 4 ) 2 BeF 4 was heated and melted with LiF at high temperature to produce Li 2 BeF 4 molten salt without separate BeF 2 preparation by pyrolysis. The obtained salt has a melting point of 458–460 °C and an oxygen content below 500 ppm. The main impure metal ion and anion concentrations are less than 10 ppm and 80 ppm, respectively. This is a convenient, efficient and economical preparative method for high-purity Li 2 BeF 4 molten salt.

C F bond activation of aliphatic fluorides provides new methodologies for synthesis of new fluorinated building blocks as well as versatile non-fluorinated products. This review covers the recent C F bond cleavage examples and further transformation of compounds bearing with an aliphatic fluoride, difluoromethylene group or trifluoromethyl groups. The methods to activate a C F bond include activation by Lewis acid, Bronsted superacids and hydrogen bonding, and mediation by transition-metals and rare earth metals. Partial reduction of trifluoromethyl group through a single electron transfer (SET) process can provide the compounds with less fluorine. Bases are often used for the elimination of hydrofluoride. S N 2′ displacement is also an important method for transformation of monofluorinated, difluorinated and trifluorinated olefins to various synthetically interesting molecules.

A new approach for the synthesis of gem -difluorostyrenes from benzyl bromide is described. Quaternization of triphenylphosphine with benzyl bromide to give phosphonium salts, deprotonation of the corresponding phosphonium salts to produce phosphonium ylide, and the subsequent olefination of phosphonium ylide with difluorocarbene generated from difluoromethylene phosphobetaine (Ph 3 P + CF 2 CO 2 − ) by decarboxylation can occur smoothly in one-pot, furnishing the final gem -difluorostyrenes in good yields.

A large number of trifluoromethylthiolation methods have been developed, but a trifluoromethylthiolation reagent usually has to be used in these methods. Herein we describe a difluorocarbene-based trifluoromethylthiolation of terminal alkynes to construct a Csp SCF3 bond catalysed by a copper complex. Ph3P+CF2CO2−/S8/F− was used as a reagent system to form the CF3S− anion, and the sequential formation of CF2 S, F CF2S and C SCF3 bonds was achieved in a one-step process.

An overview of reductive trifluoromethylation reactions using electrophilic ‘þCF3’ reagents Shi-Meng Wang , Jia-Bin Han , Cheng-Pan Zhang *, Hua-Li Qin *, Ji-Chang Xiao b,* a School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, China Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China

The past decade has witnessed the significant advances of asymmetric organocatalytic fluorination, monofluoroalkylation, gem-difluoroalkylation, and trifluoromethylation. This digest summarizes the latest progress of these reactions. In the research area of asymmetric organocatalytic fluorination, a new catalysis concept, chiral anion phase-transfer catalysis strategy, has emerged and has proved to be highly efficient. Asymmetric organocatalytic monofluoroalkylation and gem-difluoroalkylation have been much less explored and the Lewis base/acid catalysis has been the most used strategy. Compared with electrophilic trifluoromethylation, nucleophilic trifluoromethylation has been intensively studied in the research field of asymmetric organocatalytic trifluoromethylation. (C) 2014 Published by Elsevier Ltd.

Wittig reaction of aldehydes with difluoromethyltriphenylphosphonium bromide leading to gem-difluoroolefins in moderate yields is described. The reaction displays a good substrate scope including aryl, heteroaryl and alpha,beta-unsaturated aldehydes. Difluoromethyltriphenylphosphonium bromide could be easily prepared and stored for a long time under air atmosphere. The salt exhibits high thermal stability demonstrated by thermogravimetric analysis. Its structure was confirmed by NMR spectroscopy and single crystal X-ray analysis. (C) 2014 Elsevier B.V. All rights reserved.

We have developed an efficient method to achieve N-gem-difluorocyclopropylation of N-heterocycles with the use of gem-difluorocyclopropyl tosylate as a building block under mild conditions. gem-Difluorocyclopropyl tosylates could be easily prepared on a large scale and exhibit great stability.

X(CF2CF2)(5)OCF2CF2SO2F (X=I, Br, Cl; n=1, 2, 3, 4) are widely used fluoroalkylation reagents, which can incorporate 'heavy' fluorous tags into organic compounds. X(CF2CF2)OCF2CF2SO2F have both sulfonyl and halo groups. They behave as bi-functional fluoro

Both experimental and computational approaches have been employed in the present work to investigate the thermal conversion of substituted difluoro(methylene)cyclopropanes (F 2 MCP) E-1,1-difluoro-2,2-dimethyl-3-tosylmethylene cyclopropane 1 , to the thermodynamically more stable F 2 MCP products, 1,1-difluoro-2-tosyl-3-(propan-2-ylidene)cyclopropane 2 , and 1-(3-(difluoromethylene)-2,2-dimethylcyclopropylsulfonyl)-4-methylbenzene 3 . The X-ray crystal structure has been obtained for both 1 and 2 , respectively, based on which theoretical analyses on their structure and stability have been carried out. Possible reaction mechanisms are proposed.

The p K a values of a series of fluoroalkanesulfonylamides were measured by potentiometric titration. Different kinds of alkyl halides and tosylates were employed to investigate the nucleophilicity of fluoroalkanesulfonylamides. Fluoroalkanesulfonylamides with longer fluoroalkyl chain have weaker nucleophilicity.

Arylfluoroalkylsulfoxides were successfully synthesized in one-pot when fluoroalkylsulfinate reacted with benzene and triflic anhydride in triflic acid and dichloromethane as the medium. The characteristics of their 19 F NMR spectra were examined and analyzed for these structures. Electronic and steric effects of substituents at α- or β-position were revealed to be the main cause of the anomalous behavior of their chemical shifts and coupling constants. Interactions between arylfluoroalkylsulfoxides and solvents were also investigated and discussed.

Difluorocarbene generated from FSO2CF2CO2SiMe3 (TFDA) at 120 °C could reacted with terminal alkynes having an ester group at the α position to the triple bond. Difluorocyclopropenes were further converted to difluorocyclopropyl ketones under alkaline condition. Mechanism for the conversion was studied.

A series of pyrrolidinium-based salts with new fluorine-containing anions were synthesized. Different melting points could be obtained by changing the length of the fluoroalkyl chain of the anions. The pyrrolidinium 1,1,2,2-tetrafluoro-2-(1,1,2,2-tetrafluoroethoxy)ethanesulfonate ([C 4 H 8 NH 2 ][H(CF 2 ) 4 O(CF 2 ) 2 SO 3 ]) is highly fluid even below room temperature. It can be used both as a recyclable solvent and as an efficient catalyst for Friedel–Crafts alkylations of indoles with nitroalkenes.

Hexamethylphophoramide (HMPA) reacted with hexafluorobenzene and its derivatives with good conversion to give dimethylaminated products and phosphorofluoridates, even in unfavorable reaction stoichiometries. An aromatic nucleophilic mechanism might be involved. (c) 2008 Elsevier B.V. All rights reserved.

In the presence of sodium dithionite and DMSO, the intramolecular radical cyclization of 4-chloro-1,1,2,2,3,3,4,4-octafluorobutylbenzenes is achieved to give the corresponding cyclic compounds in moderate to good yields.

Treatment of tetrafluoroallene or its precursor, ICF 2 CH 2 CF 2 I, with phenols in the presence of K 2 CO 3 gave the corresponding unsaturated ethers. Tetrafluoroallene also reacted readily with amines in THF at room temperature to afford 3,3,3-trifluoropropionamides.

1-Alkyl-3-methylimidazolium fluorides were successfully synthesized by the reaction of silver fluoride with the corresponding imidazolium iodides.

A mild hydrodehalogenation reaction of fluoroalkyl halides (R f CF 2 X, X = Br, I) has been developed under weakly basic conditions, giving the corresponding hydrogenolysis products with moderate to high yields.

1. The corrected name of HCF2CF2CF2CF2OCF2CF2SO3 is ‘‘1,1,2,2tetrafluoro-2-(1,1,2,2,3,3,4,4-octafluorobutoxy)ethanesulfonate’’. Therefore, ‘‘1,1,2,2-tetrafluoro-2-(1,1,2,2-tetrafluoroethoxy)ethanesulfonate’’ in the article should be changed to ‘‘1,1,2,2tetrafluoro-2-(1,1,2,2,3,3,4,4-octafluorobutoxy)ethanesulfonate’’. 2. The missing parts for the synthesis of HCF2CF2CF2CF2OCF2CF2SO3Na and HCF2CF2CF2CF2OCF2CF2SO3H should be added to the experimental section as follows. To a stirred solution of 1,1,2,2-tetrafluoro-2-(1,1,2,2,3,3,4,4octafluorobutoxy)ethanesulfonyl fluoride (120 g, 0.3 mol) in ethanol (100 ml), the solution of sodium hydroxide (24 g, 0.6 mol) in water (100 ml) was added slowly at room temperature. Then the mixture was refluxed for 2 h. Removing the solvent under reduced pressure gave a solid. The solid was dissolved in ethyl acetate (200 ml) and the solutionwaswarmed