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Polyfluorinated substituents often enhance effectiveness, improve the stability within metabolic processes, and boost the lipophilicity of biologically active compounds. However, methods for their introduction into aliphatic carbon chains remain very limited. A potentially general route to integrate the fluorinated scaffolds into organic molecules involves insertion of fluorine‐containing carbenes into C(sp3)−H bonds. The electron‐withdrawing characteristics of perfluoroalkyl groups enhances the reactivity of these carbenes which should enable the functionalization of unactivated C(sp3)−H bonds. Curiously, it appears that use of perfluoroalkyl‐containing carbenes in alkane C−H functionalization is exceedingly rare. This concept describes photolysis, enzymatic catalysis, and transition metal catalysis as three primary approaches to C(sp3)−H functionalization by trifluoromethylcarbene and its homologues. [ABSTRACT FROM AUTHOR]

We report here "sandwich"‐diimine copper complex‐catalyzed trifluoroethylation and pentafluoropropylation of unactivated C(sp3)−H bonds in alkyl esters, halides, and protected amines by employing CF3CHN2 and CF3CF2CHN2 reagents. Reactions proceed in dichloromethane solvent at room temperature. Identical C−H functionalization conditions and stoichiometries are employed for generality and convenience. Selectivities for C−H insertions are higher for compounds possessing stronger electron‐withdrawing substituents. Preliminary mechanistic studies point to a mechanism involving a pre‐equilibrium forming a "sandwich"‐diimine copper‐CF3CHN2 complex followed by rate‐determining loss of nitrogen affording the reactive copper carbene. It reacts with trifluoromethyldiazomethane about 6.5 times faster than with 1‐fluoroadamantane explaining the need for slow addition of the diazo compound. [ABSTRACT FROM AUTHOR]

We report here "sandwich" diimine‐copper(I) catalysts for C(sp3)−H bond functionalization. Reactions of alkanes and ethers with trimethylsilyldiazomethane, ethyl diazoacetate, and trifluoromethyl‐diazomethane have been demonstrated. We also report C(sp3)−H bond methylation, benzylation, and diphenylmethylation by diazomethane, aryldiazomethanes, and diphenyldiazomethane. These reactions are rare examples of base‐metal catalyzed, intermolecular C(sp3)−H functionalizations by employing unactivated diazo compounds. Electrophilicity and unique steric environment of "sandwich"‐copper catalysts are likely reasons for their catalytic efficiency. [ABSTRACT FROM AUTHOR]

Four extensively fluorinated tetraphenylethylenes (TPE) and one extensively fluorinated triphenylethylene have been synthesized using combinations of copper‐catalyzed C−H functionalization reactions and Stille coupling reactions. Surprisingly, in contrast to the parent TPE, these compounds show little to no aggregation‐induced emission (AIE). Instead, photocyclization into fluorinated phenanthrene products occurs. Effects of solvent and oxygen on the yield and selectivity of this photocyclization have been examined. [ABSTRACT FROM AUTHOR]

The reactivity of NiII and PdII olefin polymerization catalysts can be enhanced by introduction of electron‐withdrawing substituents on the supporting ligands rendering the metal centers more electrophilic. Reported here is a comparison of ethylene polymerization activity of a classical salicyliminato nickel catalyst substituted with the powerful electron‐withdrawing 2,4,6‐triphenylpyridinium (trippy) group to the ‐CF3 analogue. The trippy substituent is substantially more electron‐withdrawing (σmeta=0.63) than the trifluoromethyl group (σmeta=0.43) which results in a ca. 8‐fold increase in catalytic turnover frequency. An additional advantage of trippy is the high steric bulk relative to the trifluoromethyl group. This feature results in a four‐fold increase in polymer molecular weight owing to enhanced retardation of chain transfer. A significant increase in catalyst lifetime is observed as well. [ABSTRACT FROM AUTHOR]

Abstract: A method for cobalt‐catalyzed, carboxylate‐directed functionalization of arene C−H bonds is reported. Alkynes, styrenes, and 1,3‐dienes can be coupled with benzoic acids to provide cyclic products in good yields. The reactions proceed in the presence of a cobalt(II) hexafluoroacetylacetonate catalyst, (TMS)2NH base, Ce(SO4)2 cooxidant, and oxygen oxidant. [ABSTRACT FROM AUTHOR]

We have developed a method for palladium-catalyzed, pyrazole-directed sp3 C−H bond arylation by aryl iodides. The reaction employs a Pd(OAc)2 catalyst at 5-10 mol % loading and silver(I) oxide as a halide-removal agent, and it proceeds in acetic acid or acetic acid/hexafluoroisopropanol solvent. Ozonolysis of the pyrazole moiety affords pharmaceutically important β-phenethylamines. [ABSTRACT FROM AUTHOR]

We report structural characterization of a new member of m-phenylene ethynylene ring family. This shape-persistent macrocycle also co-crystallizes with hexafluoro-, 1,2,4,5-tetrafluoro-, 1,3,5-trifluoro, and 1,4-difluorobenzene. The four complexes are almost isostructural, and all show the fluoroarene included into the central cavity of the macrocycle. Characterized by multiple short CH⋅⋅⋅FC contacts, these inclusion complexes further dimerize in the solid state into a 2+2 assembly, in which the two macrocycles embrace each other by their large hydrophobic groups that are rotated by 60° relative to one another. [ABSTRACT FROM AUTHOR]

A method for cobalt-catalyzed, aminoquinoline- and picolinamide-directed C(sp2)H bond alkenylation by alkynes was developed. The method shows excellent functional-group tolerance and both internal and terminal alkynes are competent substrates for the coupling. The reaction employs a Co(OAc)2⋅4 H2O catalyst, Mn(OAc)2 co-catalyst, and oxygen (from air) as a terminal oxidant. [ABSTRACT FROM AUTHOR]

Amine meets arene: A method for direct amination of β‐C(sp2)H bonds of benzoic acid derivatives and γ‐C(sp2)H bonds of benzylamine derivatives has been developed. The reaction is catalyzed by Cu(OAc)2 and a Ag2CO3 cocatalyst, and shows high generality and functional‐group tolerance, as well as providing a straightforward means for the preparation of ortho‐aminobenzoic acid derivatives. [ABSTRACT FROM AUTHOR]

Review: 169 refs. [ABSTRACT FROM AUTHOR]

Primary, secondary, and aromatic amines, heterocycles as well as electron-deficient aromatic and heteroaromatic are employed as amine coupling partners using Cu(OAc)2 or CuCO3·Cu(OH)2 as catalysts and oxygen from the air as the terminal oxidant. [ABSTRACT FROM AUTHOR]

An abstract of the article "Cobalt-Promoted Dimerization of Aminoquinoline Benzamides" by Liene Grigorjeva and Olafs Daugulis is presented.

Review: 75 refs. [ABSTRACT FROM AUTHOR]

The optimized procedure comprises air-oxygen as terminal oxidant and Mn(O-Ac)2 as co-catalyst to produce isoquinoline scaffolds which are of interest in pharmaceutical and natural product syntheses. [ABSTRACT FROM AUTHOR]

The coupling of N-(8-quinolinyl) substituted amides with olefins is developed using air as the oxidant. [ABSTRACT FROM AUTHOR]

A method for the cobalt catalyzed carbonylation of N-(8-quinolyl) substituted benzamides and acrylamides is developed using air as the oxidant in the presence of Mn(OAc)3 as promoter. [ABSTRACT FROM AUTHOR]

A shape ‐ persistent macrocycle from the m ‐ phenylene ethynylene family is capable of encapsulating 1,2 ‐ difluorobenzene, 1,3,5 ‐ trifluorobenzene, 1,2,4,5 ‐ tetrafluorobenzene, and hexafluorobenzene, in an almost isostructural arrangement, which places the fluoroarene into the cavity of the macrocycle. Curiously, symmetries of the (pseudo)hexagonal host and its guests do not have to be matched; this combination of various symmetries is reminiscent of the arabesques of Alhambra, as shown in the artist′s rendition. For more details, see the Full Paper by O. Š. Miljanić et al. page 2750 ff. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for article "Copper-Catalyzed Etherification of Arene C?H Bonds" by J. Roane and colleagues, published in "Organic Letters" in 2013 issue.

The deployment of different bases determines the reaction pathway: either formation of helicenes or ortho-arylation of phenols. [ABSTRACT FROM AUTHOR]

The present arylation of anilines proceeds selectively at the ortho-position. [ABSTRACT FROM AUTHOR]

Syntheses of substituted phenylalanine derivatives (III) are highly convergent and employ an N-phthaloylalanine with a 2-thiomethylaniline directing group. [ABSTRACT FROM AUTHOR]