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The selective N-arylation of p-aminophenylalanine in polypeptides with pre-formed palladium oxidative addition complexes is described. The depressed pKa of the aniline NH2 group enables chemoselective C-N bond formation on peptides containing multiple other aliphatic amino groups at lysines or the N-terminus via Curtin-Hammett control under mild conditions. Using palladium complexes derived from electron-poor aryl halides, p-aminophenylalanine is fully arylated in aqueous buffer in as little as one hour at micromolar concentrations. A complementary protocol using the non-nucleophilic, organic base 1,5-diazabicyclo(4.3.0)non-5-ene (DBN), expands the substrate scope to tolerate electron-rich functional groups provides up to 97 % conversion. These procedures enable the chemoselective conjugation of functionally diverse small molecule pharmaceuticals to p-aminophenylalanine containing derivatives of cell-penetrating peptides.

The asymmetric hydroaminocarbonylation of olefins represents a straightforward approach for the synthesis of enantioenriched amides, but is hampered by the necessity to employ CO gas, often at elevated pressures. We herein describe, as an alternative, an enantioselective hydrocarbamoylation of alkenes leveraging dual copper hydride and palladium catalysis to enable the use of readily available carbamoyl chlorides as a practical carbamoylating reagent. The protocol is applicable to various types of olefins, including alkenyl arenes, terminal alkenes, and 1,1-disubstituted alkenes. Substrates containing a diverse range of functional groups as well as heterocyclic substructures undergo functionalization to provide α- and β-chiral amides in good yields and with excellent enantioselectivities.

In Pd-catalyzed C[BOND]N cross-coupling reactions, α-branched secondary amines are difficult coupling partners and the desired products are often produced in low yields. In order to provide a robust method for accessing N-aryl α-branched tertiary amines, new catalysts have been designed to suppress undesired side reactions often encountered when these amine nucleophiles are used. These advances enabled the arylation of a wide array of sterically encumbered amines, highlighting the importance of rational ligand design in facilitating challenging Pd-catalyzed cross-coupling reactions., National Institutes of Health (U.S.) (Grant GM58160), National Science Foundation (U.S.). Graduate Research Fellowship Program

A general, efficient method for C-N cross-coupling has been developed using N,N-dimethyloctanamide as a catalytic cosolvent for biphasic continuous-flow applications. The described method was used to generate a variety of biarylamines and was integrated into a two-step sequence which converted phenols into biarylamines via either triflates or tosylates. Additionally, the method was applied to a three-step synthesis of imatinib, the API of Gleevec, in good yield without the need of solvent switches.

Something radical: An efficient enantioselective oxytrifluoromethylation of alkenes has been developed using a copper catalyst system. Mechanistic studies are consistent with a metal-catalyzed redox radical addition mechanism in which a C[BOND]O bond is formed by the copper-mediated enantioselective trapping of a prochiral alkyl radical intermediate derived from the initial trifluoromethyl radical addition., National Institutes of Health (U.S.) (Award GM46059)

In den vergangenen Jahren wurde die CuH-katalysierte Hydroaminierung entdeckt und als robuster und konzeptionell neuer Synthesezugang zu enantiomerenangereicherten sekundaren und tertiaren Aminen entwickelt. Der Erfolg auf diesem Gebiet wurde moglich durch zahlreiche fruhere Beispiele fur die Katalyse mit Kupfer(I)hydrid und die gut untersuchte Verwendung von Hydroxylaminestern als elektrophile Aminquellen in ahnlichen kupferkatalysierten Reaktionen. Dieser Kurzaufsatz beschreibt Hintergrund, Fortschritte und mechanistische Untersuchungen der CuH-katalysierten Hydroaminierung.

What N would you like? The chemoselective and complementary Pd- and Cu-catalyzed N-arylation of 2-aminobenzimidazoles is described. Selective N-arylation of the amino group was achieved with a Pd-catalyzed method, while selective N-arylation of azole nitrogen was achieved with a Cu-catalyzed procedure (see scheme)., National Institutes of Health (U.S.) (GM58160)

An efficient protocol has been developed for the intramolecular oxidative oxyarylation using a Pd[superscript II]-catalyzed tandem oxypalladation/C-H functionalization strategy. This methodology allows rapid access to tetrahydro-2H-indeno-[2,1-b]furan frameworks from simple hydroxyalkenes. The reactivity of this process is orthogonal to that of Pd[superscript 0]-catalyzed transformations, enabling the divergent modification of a single molecule., National Institutes of Health (U.S.) (GM46059), National Institutes of Health (U.S.) (Grant 1S10RR13886-01), National Science Foundation (U.S.) (CHE-0946721)

A general, rapid, and efficient method for the copper-catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described method can tolerate a broad spectrum of functional groups, including N-H and O-H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous-flow processes (amidation and Mg-I exchange/nucleophilic addition) to demonstrate the flexibility of this method.

Good to excellent yields of aryl trifluoromethyl sulfides, which are an important class of compounds in both the pharmaceutical and agrochemical areas, can be achieved under mild conditions by the Pd-catalyzed reaction of aryl bromides with a trifluoromethylthiolate nucleophile (see scheme)., National Institutes of Health (U.S.) (GM-58160), American Society for Engineering Education. National Defense Science and Engineering Graduate Fellowship (32 CFR 168a), National Science Foundation (U.S.) (CHE-980861)

Highly N2-selective arylation of 4,5-unsubstituted and 4-substituted 1,2,3-triazoles was achieved for the first time by Pd/L1 catalyst system. A wide range of N2-aryl-1,2,3-triazoles were prepared from aryl bromides, chlorides and triflates with excellent (95–99%) N2-selectivity. DFT calculations suggest that formation of N2-arylated 1,2,3-triazoles is favored kinetically.

In den vergangenen 12 Jahren erfuhr die palladiumkatalysierte Aminierung von Arylhalogeniden eine rasche Entwicklung, die durch die Einfuhrung neuer Ligandenklassen vorangetrieben wurde. Biarylphosphane liefern in diesem Zusammenhang besonders reaktive Katalysatoren. Dieser Aufsatz behandelt Anwendungen solcher Katalysatoren zur C-N-Kreuzkupplung in der Synthese von Heterocyclen und Pharmazeutika, in den Materialwissenschaften und in der Naturstoffsynthese.