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The continuous flow reaction of various aryl or heteroaryl bromides in toluene in the presence of THF (1.0 equiv) with sec-BuLi (1.1 equiv) provided at 25 °C within 40 sec the corresponding aryllithiums which were acylated with various functionalized N,N-

A double-enzyme-catalyzed strategy for the synthesis of enantiocomplementary vicinal fluoro alcohols through a one-pot, three-step process including lipase-catalyzed hydrolysis, spontaneous decarboxylative fluorination, and subsequent ketoreductase-catalyzed reduction was developed. With this approach, β-ketonic esters were converted to the corresponding vicinal fluoro alcohols with high isolated yields (up to 92percent) and stereoselectivities (up to 99percent). This new cascade process addresses some issues in comparison with traditional methods such as environmentally hazardous reaction conditions and low stereoselectivity outcome.

Fluorinated acyl-Meldrum's acid derivatives were synthesized by electrophilic fluorination of appropriate phenacyl Meldrum's acid substrates using Selectfluor. Reactions with water, ethanol, Grignard, and alkynyllithium reagents gave rise to the correspon

Cesium carbonate (Cs2CO3)-mediated decarboxylative fluorination of β-ketoacids using NFSI in the MeCN/H2O mixed solvent system affords α-fluoroketones with a broad scope. Both electron-rich and electron-deficient α-non-substituted β-ketoacids are amenable to this protocol. The mechanistic study indicates that the reaction proceeds through electrophilic fluorination followed by decarboxylation, which is different from the decarboxylative fluorination of normal carboxylic acids.

A palladium catalyzed Negishi-type α-arylation of α-fluoroketones with electron-rich and electron-deficient aryl halides or phenyl triflate has been developed. This direct mono-α-arylation method generate a variety of ternary α-aryl-α-monofluoroketones easily in good to excellent yields using XPhos as ligand and Cs2CO3as mild base.

An efficient and mild fluorination of vinyl azides for the synthesis of α-fluoroketones is described. The mechanistic studies indicated that a single-electron transfer (SET) and a subsequent fluorine atom transfer process could be involved in the reaction.

Reported is an efficient synthesis of α-fluoroketones by insertion of hydrogen fluoride (HF) into the gold carbene intermediate, generated from a cationic gold catalyzed addition of N-oxides to alkynes. This method results in excellent chemical yields for a wide range of alkyne substrates and demonstrates good functional-group tolerance.

Transaminases are valuable enzymes for industrial biocatalysis and enable the preparation of optically pure amines. For these transformations they require either an amine donor (amination of ketones) or an amine acceptor (deamination of racemic amines). Herein transaminases are shown to react with aromatic β-fluoroamines, thus leading to simultaneous enantioselective dehalogenation and deamination to form the corresponding acetophenone derivatives in the absence of an amine acceptor. A series of racemic β-fluoroamines was resolved in a kinetic resolution by tandem hydrodefluorination/deamination, thus giving the corresponding amines with up to greater than 99 % ee. This protocol is the first example of exploiting the catalytic promiscuity of transaminases as a tool for novel transformations.

A facile and mild one-pot protocol via decarboxylation of trifluoromethyl β-diketones has been developed for the construction of α-fluoroketones and 3-fluoro-2,4-diarylfurans which are important units in many biologically active compounds and useful precursors in a variety of functional-group transformations.

A novel oxyfluorination of olefin reactions has been developed. The reactions involve a metal-free and green catalytic system for the synthesis of α-fluoroketones which is an important building block for organic synthesis. Moreover, this reaction system exhibits great functional group tolerance.

An efficient synthesis of α-fluoroketones via the nucleophilic fluorination of α-bromoketones in water with TBAF·3H2O as the fluorinating agent was developed in this paper. In addition, a simple and efficient synthesis of α-fluoroenones through the condensation of α-fluoroketones with aldehydes promoted by sodium hydroxide in water was also discovered.

The use of purified and overexpressed alcohol dehydrogenases to synthesize enantiopure fluorinated alcohols is shown. When the bioreductions were performed with ADH-A from Rhodococcus ruber overexpressed in E. coli, no external cofactor was necessary to obtain the enantiopure (R)-derivatives. Employing Lactobacillus brevis ADH, it was possible to achieve the synthesis of enantiopure (S)-fluorohydrins at a 0.5 M substrate concentration. Furthermore, due to the activated character of these substrates, a huge excess of the hydrogen donor was not necessary.

Two methods of nucleophilic fluorination to prepare α-fluoroacetophenones from α-bromoacetophenones by using KF with PEG-400 or TBAF with ZnF2 are described. On the fundamental of nucleophilic fluorination, a novel method of one-pot fluorination to prepare α-fluoroacetophenones directly from acetophenones in DES was developed.

The first examples of asymmetric transfer hydrogenation of α-fluoroacetophenones are reported. Eight para-substituted α-fluoroacetophenones have been reduced using four catalytic systems constructed of [RuCl2(p-cymene)2]2 or [RuCl2(mesitylene)2]2 in combinations with each of the ligands (1R,2R)-N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine ((R,R)-TsDPEN) and (1R,2R)-N-(p-toluenesulfonyl)-1,2-cyclohexanediamine ((R,R)-TsCYDN). All reactions were performed in both water and formic acid/triethylamine. The highest enantioselectivity was obtained using the (R,R)-TsDPEN ligand in a formic acid/triethylamine mixture, giving the (S)-1-aryl-2-fluoroethanols in high to moderate enantiomeric excess (97.5-84.5%). For this solvent system the presence of electron withdrawing groups in the para position reduced the enantioselectivity. Reactions performed in water generally gave lower enantioselectivity and reaction rate, although RuCl(mesitylene)-(R,R)-TsDPEN yielded the product alcohols with enantiomeric excess in the range of 95.5-76.5%.

A two-step, one-pot microwave (MW) assisted fluorination of 1-arylethanones to their corresponding 1-aryl-2-fluoroethanones has been developed. The first step utilises Selectfluor as a fluorinating agent in methanol forming 1-aryl-2-fluoroethanones and their corresponding dimethyl acetals. In the second step, water is added and Selectfluor acts as a Lewis acid in the hydrolytic cleavage of the dimethyl acetals. Compared to the thermal synthesis, the MW assisted method leads to a reduction in reaction time both in the fluorination and for the dimethyl acetal cleavage. Moreover, the one-pot procedure reduces reagent and solvent consumption. The method is best suited for the preparation of 1-aryl-2-fluoroethanones containing substituents that deactivates electrophilic aromatic substitution, however highly electron deficient ketones such as 1-(3,5-dinitrophenyl)ethanone reacts more slowly. Reactions using electron rich aromatic ketones had a low regioselectivity, and also produced fluoroaromatic products.

para-Substituted α-fluoroacetophenones have been synthesised by three different routes. Electrophilic fluorination of trimethylsilyl enol ethers of acetophenones using Selectfluor (F-TEDA-BF4, 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis-(tetrafluoroborate)) gave high to moderate yield depending on the electronic properties of the substituents. F-TEDA-BF4 mediated fluorination of acetophenones in methanol resulted in a mixture of α-fluoroacetophenones and the corresponding 2-fluoro-1,1-dimethyl acetals. The dimethyl acetals were hydrolysed using trifluoroacetic acid in water to maximise the yield of the product. Nucleophilic fluorination of α-bromoacetophenones using tetrabutylammonium hydrogen bifluoride (TBABF) led to moderate yield when having electron-donating substituents, whereas low yields were experienced when more electron-withdrawing substituents were introduced.

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Process for preparing an organic compound of the formula R2 R2 CFC(O)R3, which process comprises contacting and reacting in a reaction mixture which includes an inert solvent, at a temperature of -40° C. to -100° C., ROF and STR1 R is polyfluoroperhaloalkyl of 1-6 carbon atoms or FOCF2 ; R1 is hydrocarbyl of 1-6 carbon atoms; each R2 is selected from H, alkyl of 1-17 carbon atoms, cycloalkyl of 3-6 carbon atoms, aryl, heteroaryl and such alkyl, cycloalkyl, aryl and heteroaryl substituted by halogen or alkoxy of 1-6 carbon atoms; R3 is selected from H, alkyl and haloalkyl of 1-16 carbon atoms, cycloalkyl of 3-10 carbon atoms, aryl and haloaryl, OSi(R1)3, OH, NH2, alkoxy of 1-6 carbon atoms, aryloxy, NHR1 and NR12 wherein R1 is alkyl of 1-6 carbon atoms, N-arylamino and nitrogen or sulfur heterocyclic of 4-5 carbon atoms; R3 and one R2 taken together is a diradical which with the C=C group is carbocyclic, heterocyclic or haloheterocyclic, and recovering from the reaction mixture the compound of the formula R2 R2 CFC(O)R3.