Chan–Evans–Lam N1-(het)arylation and N1-alkеnylation of 4-fluoroalkylpyrimidin-2(1H)-ones

The Chan–Evans–Lam reaction of 1-unsubstituted 4-fluoroalkylpyrimidin-2(1Н)-ones with arylboronic acids is reported as a facile synthetic route to hitherto unavailable N1-(het)aryl and N1-alkenyl derivatives of the corresponding pyrimidines. An efficient C–N bond-forming process is also observed by using boronic acid pinacol esters as coupling partners in the presence of Cu(II) acetate and boric acid. The 4-fluoroalkyl group on the pyrimidine ring significantly assists in the formation of the target N1-substituted products, in contrast to the 4-methyl and 4-unsubstituted substrates which do not undergo N1-arylation under similar reaction conditions.

Late-stage trifluoromethylthiolation of benzylic C-H bonds

The benzylic positions in drugs are sites that readily react with cytochrome P450 oxidases via single-electron oxidation. New synthetic methodologies to incorporate a fluoroalkyl group at the benzylic site are continually being developed, and in this paper, we report a metal-free and site-selective organophotoredox-catalyzed trifluoromethylthiolation of benzylic C-H bonds for a wide variety of alkyl arenes and heteroarenes. The precise and predictive regioselectivity among various C(sp3)-H bonds originates from an inner-sphere benzylic radical initiation mechanism, and avoids the use of external oxidants or hydrogen atom abstractors. Its practicality stems from the trifluoromethylthiolation of a series of drugs and complex organic molecules, which is overwhelmingly selective for benzyl groups. This operationally simple protocol can provide a general and practical access to structurally diverse benzylic trifluoromethyl sulfides produced from ubiquitous benzylic C-H bonds. Large scale trifluoromethylthiolation can be achieved with continuous flow photoredox technology.

Preparation of fluoropolymer with gem-bis-fluoroalkylated side-chain and its application on cotton fabric finishing

In this study, three types of fluorinated polyacrylates (PBFB, PBFS, and PMFA) were synthesized by 4-gem-bis(2,2,3,3,4,4,5,5,5-nonafluoropentyl)-1-butene, 4-gem-bis(2,2,3,3,4,4,5,5,5-nonafluoropentyl)-methine-1-styrene, and 3,3,4,4,5,5,6,6,6-nonafluorohexyl acrylate, respectively, as monomers via emulsion polymerization. Particle size, particle size distribution, and zeta potential were tested to assess the emulsion stability. Afterwards, the latexes were coated onto fabrics to obtain gem-bis(fluoroalkyl)-cotton. The surface properties of the treated cotton fabrics were analyzed by X-ray photoelectron spectroscopy and water contact angle. It was found that, when controlling the fluorine content level to be similar, the water contact angles of gem-bis(fluoroalkyl)-cottons were 127° ± 0.5° and 134.9° ± 0.7°, respectively, which were both higher than that of mono-fluoroalkyl-cotton (PMFA-cotton of 125.2° ± 0.2°). This showed that gem-bis-fluoroalkyl groups could provide better hydrophobic performance than the mono-fluoroalkyl group, especially when the rigid benzene was used as a side-chain bridged group.

Highly Regio- and Stereoselective Hydrogermylation of Fluorinated Alkyl Propiolate

The selective introduction of fluoroalkylated vinylmetals in controlled strategies is a challenging process for many chemists. This study reports the highly regio- and stereoselective synthesis of functionalized vinylgermanes bearing a perfluoroalkyl group from per­fluoroalkylated acetylenic esters via AlCl3-catalyzed hydrogermylation. Regio- and stereoselectivity are highly dependent on the nature of the catalyst and the nature of the fluoroalkyl group of alkyne.

Synthesis of water-soluble hypervalent iodine reagents for fluoroalkylation of biological thiols

New activated and water-soluble hypervalent iodine reagents were synthesized and used for fluoroalkyl group transfer to cysteine and in reactions with disulfides.

Iron-Catalyzed Carboiodination of Alkynes

An iron-catalyzed carboiodination of alkynes with alkyl iodides­ at room temperature was developed. This method could provide synthetically useful vinyl iodides with general alkyl chains, fluoroalkyl group, ester, and cyano group. Conjugated alkynes or unconjugated alkynes were both suitable for this transformation. A radical pathway was proposed for the mechanism and acetyl tert-butyl peroxide was selected as the radical initiator. Alkenes could also be applied to this chemistry and produce more complex alkyl iodides.

The unique fluorine effects in organic reactions: recent facts and insights into fluoroalkylations

Fluoroalkylation reaction, featuring the transfer of a fluoroalkyl group to a substrate, is a straightforward and efficient method for the synthesis of organofluorine compounds. In fluoroalkylation reactions, fluorine substitution can dramatically influence the chemical outcome.

An efficient catalyst-free Mukaiyama-aldol reaction of fluorinated enol silyl ethers with tryptanthrin

We report an efficient Mukaiyama-aldol reaction of tryptanthrin with fluorinated enol silyl ethers, which is carried out in methanol without the use of any catalyst. This represents the first modification of tryptanthrin by a fluoroalkyl group, which is applied to the total synthesis of the difluoro analogues of the natural product Phaitanthrin B.