Fluoroalkyl Bromides Research Articles

Bioinspired photocatalysed C–H fluoroalkylation of arenes in water promoted by native vitamin B12 and Rose Bengal

Fluoroalkylation of activated arenes was accomplished in water employing the dyad Rose Bengal and unmodified vitamin B12 as photocatalyst and co-catalyst respectively, with fluoroalkyl bromides as radical sources, under green LEDs irradiation.

Photo-triggered self-catalyzed fluoroalkylation/cyclization of unactivated alkenes: synthesis of quinazolinones containing the CF2R group

A photo-triggered self-catalyzed fluoroalkylation/cyclization of quinazolinones containing unactivated alkenes with various fluoroalkyl bromides has been developed.

Atom-transfer radical addition of fluoroalkyl bromides to alkenes via a photoredox/copper catalytic system.

A method for the addition of fluorinated alkyl bromides to alkenes is described. The reaction proceeds under visible light irradiation in the presence of two catalysts: Ir(ppy)3 and N-heterocyclic carbene ligated copper bromide (IMesCuBr). The role of the iridium photocatalyst is to generate the fluoralkyl radical, while the copper promotes formation of the carbon-bromine bond.

Copper‐Catalyzed C−H Difluoroalkylation of Coumarins with Fluoroalkyl Bromides

AbstractAn efficient method for the copper‐catalyzed selective C−H difluoroalkylation of coumarins and with low cost and readily available ethyl bromodifluoroacetate and N‐phenyl bromodifluoroacetamide has been reported. This reaction exhibits good functional group tolerance with respect to coumarins and difluoroalkylation reagents, and several redox‐sensitive substrates have been successfully C−H difluoroalkylated in good to high yield. This design could further expand the scope to other heteroarenes, including furan, benzofuran, pyrrole, pyridinone, chromenone, indole, and quinolinone. A mechanism involving copper‐catalyzed in‐situ generation of fluoroalkyl radical is proposed.

Switching between Copper‐Catalysis and Photocatalysis for Tunable Halofluoroalkylation and Hydrofluoroalkylation of 1,6‐Enynes toward 1‐Indenones

AbstractTunable halofluoroalkylation and hydrofluoroalkylation of 1,6‐enynes were first reported by switching between copper‐catalysis and photocatalysis, leading to the atom‐economic and highly stereoselective protocols toward functionalized 1‐indenones with moderate to good yields. Copper‐catalysis enabled the concomitant incorporation of two important fluoroalkyl and halo functionalities into 1‐indenone skeleton, in which fluoroalkyl bromides were transformed into (E)‐1‐indenones as a major stereoisomer while fluoroalkyl iodides oriented complete Z‐selectivity to access (Z)‐1‐indenones. Specifically, photocatalysis allowed hydrofluoroalkylation of 1,6‐enynes to access fluoroalkylated (Z)‐1‐indenones under mild conditions, in which THF behaved as a hydrogen source. These two approaches feature remarkable compatibility with a wide variety of 1,6‐enynes and fluoroalkyl halides and excellent atomic utilization.magnified image

Zinc‐Mediated Intermolecular Reductive Radical Fluoroalkylsulfination of Unsaturated Carbon–Carbon Bonds with Fluoroalkyl Bromides and Sulfur Dioxide

A versatile and general zinc-mediated intermolecular reductive radical fluoroalkylsulfination of unsaturated C-C bonds has been developed using readily available fluoroalkyl bromides and 1,4-diazabicyclo[2.2.2]octane-bis(sulfur dioxide) adduct (DABSO) with wide substrate scope and excellent functional group tolerance. Sulfur dioxide anion radical generated in situ from the reduction of sulfur dioxide with zinc may be involved in the reaction mechanism.

Nickel-Catalyzed Regioselective C(2)-H Difluoroalkylation of Indoles with Difluoroalkyl Bromides.

Regioselective C(2)-H difluoroalkylation of C-3 unsubstituted indoles with commonly available fluoroalkyl bromides is successfully achieved employing a simple nickel catalyst system, (DME)NiCl2 /Xantphos. This methodology shows excellent regioselectivity and exhibits a broad substrate scope. Various functional groups, such as -OMe, -F, and -Br, are tolerated on the indole backbone to give the difluoroalkylated products in moderate to good yields. Preliminary mechanistic findings demonstrate that the reaction is homogeneous in nature and involves a radical manifold. Synthetic utility of this nickel-catalyzed method is demonstrated by synthesizing melatonin receptor antagonist Luzindole derivative.

Synthesis of Difluoromethylated and Phosphorated Spiro[5.5]trienones via Dearomative Spirocyclization of Biaryl Ynones.

Copper- or silver-catalyzed cascade radical addition/dearomative spirocyclization of biaryl ynones with fluoroalkyl bromides or diethylphosphite has been realized for the first time. This method provides a novel and step-economical protocol for the divergent synthesis of a wide range of difluoromethylated or monofluoromethylated and phosphorated spiro[5.5]trienones in moderate to high yields.

Palladium‐Catalyzed Remote Aryldifluoroalkylation of Alkenyl Aldehydes

AbstractA palladium‐catalyzed three‐component reaction between fluoroalkyl bromides, arylboronic acids, and alkenyl aldehydes has been developed and provides facile access to 5‐, 6‐, or 7‐difluoroalkylated ketones under very mild reaction conditions. The resultant products can be smoothly converted into CF2‐containing tetrahydronaphthalenes by a novel silver‐catalyzed intramolecular decarboxylative cyclization of 5‐aryl‐2,2‐difluoropentanoic acids.

Palladium-Catalyzed Remote Aryldifluoroalkylation of Alkenyl Aldehydes.

A palladium-catalyzed three-component reaction between fluoroalkyl bromides, arylboronic acids, and alkenyl aldehydes has been developed and provides facile access to 5-, 6-, or 7-difluoroalkylated ketones under very mild reaction conditions. The resultant products can be smoothly converted into CF2 -containing tetrahydronaphthalenes by a novel silver-catalyzed intramolecular decarboxylative cyclization of 5-aryl-2,2-difluoropentanoic acids.

ChemInform Abstract: A General Synthesis of Fluoroalkylated Alkenes by Palladium‐Catalyzed Heck‐Type Reaction of Fluoroalkyl Bromides.

AbstractThis is the first example of a Pd(II)‐catalyzed Heck‐type reaction of alkenes with perfluoroalkyl halides.

A general synthesis of fluoroalkylated alkenes by palladium-catalyzed Heck-type reaction of fluoroalkyl bromides.

An efficient palladium-catalyzed Heck-type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences.

A General Synthesis of Fluoroalkylated Alkenes by Palladium‐Catalyzed Heck‐Type Reaction of Fluoroalkyl Bromides

AbstractAn efficient palladium‐catalyzed Heck‐type reaction of fluoroalkyl halides, including perfluoroalkyl bromides, trifluoromethyl iodides, and difluoroalkyl bromides, has been developed. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, and provides a general and straightforward access to fluoroalkylated alkenes which are of interest in life and material sciences.