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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]

A new class of chiral phosphines belonging to the P-aryl-2-phosphabicyclo octane family (PBO) is prepared by enantioselective synthesis starting from lactate esters and 2,2-dimethylcyclopentanone enolate. A substantial effort was invested to probe the relationship between catalyst purity and enantioselectivity.

N-Iminopyridinium ylides are competent monodentate directing groups for cobalt-catalysed annulation of sp2 C–H bonds with internal alkynes. The pyridine moiety in the ylide serves as an internal oxidant and is cleaved during the reaction. The annulation reactions possess excellent compatibility with heterocyclic substrates, tolerating furan, thiophene, pyridine, pyrrole, pyrazole, and indole functionalities. [ABSTRACT FROM AUTHOR]

A method is developed for auxiliary-directed, palladium-catalyzed [beta]-arylation and alkylation of [sp.sup.3] and [sp.sup.2] C-H bonds in carboxylic acid derivatives. 8-Aminoquinoline auxiliary has produced the best results for alkylation of [sp.sup.3] and [sp.sup.2] C-H bonds, where functional group tolerance is observed and amino- and hydroxyl-acid derivatives are functionalized.

Microfluidics is used for implementing genetic algorithms (GA) for discovering new homogeneous catalysts by using the oxidation of methane by molecular oxygen as a model system. The Pt/Fe system has shown the compatibility of iron with the entire catalytic cycle and the approach of GA-guided evolution has the potential to accelerate the discovery in catalysis and other areas

A general method is developed for copper-catalyzed deprotonative dimerization of arenes by using oxygen as the terminal oxidant. The electron-rich and electron-poor heterocycles as well as electron-poor arenes are reactive and the method is tolerant to functionalities like nitro, cyano, dialkylamino and ester groups.

A general method is developed for in situ trapping of arylmetal intermediates by halogen, sulfur, ketone and aldehyde electrophiles, which has produced the functionalization of the most acidic position in arene. [K.sub.3]P[O.sub.4] base is used for functionalizing pentafluorobenzene, benzothiazole and benzoxazole.

A general method is developed for copper-catalyzed arylation of [sp.sup.2] C-H bonds with p[K.sub.a]'s below 35. Electron-poor arenes possessing at least two electron-withdrawing groups on a benzene ring is arylated and two arylcopper-phenanthroline complex intermediates are prepared independently.

The development a palladium-catalyzed benzamide sequence ortho-arylation/rection with [(C[F.sub.3]CO).sub.2]O for convenient one-pot synthesis of ortho-arylated benzonitriles and fluorenone derivatives is reported. The N-propyl benzamides is converted to fluorenones while N-cyclohexyl benzamides yield benzonitrile derivatives.