Buchwald-Hartwig reaction: An overview

Identification of Isoform 2 Acid-Sensing Ion Channel Inhibitors as Tool Compounds for Target Validation Studies in CNS

Acid-sensing ion channels (ASICs) are a family of ion channels permeable to cations and largely responsible for the onset of acid-evoked ion currents both in neurons and in different types of cancer cells, thus representing a potential target for drug discovery. Owing to the limited attention ASIC2 has received so far, an exploratory program was initiated to identify ASIC2 inhibitors using diminazene, a known pan-ASIC inhibitor, as a chemical starting point for structural elaboration. The performed exploration enabled the identification of a novel series of ASIC2 inhibitors. In particular, compound 2u is a brain penetrant ASIC2 inhibitor endowed with an optimal pharmacokinetic profile. This compound may represent a useful tool to validate in animal models in vivo the role of ASIC2 in different neurodegenerative central nervous system pathologies.

Cu(II)-Mediated N-H and N-Alkyl Aryl Amination and Olefin Aziridination

Cu(II)-mediated direct NH₂ and NH alkyl aryl aminations and olefin aziridinations are described. These room-temperature, one-pot, environmentally friendly procedures replace costly Rh₂ catalysts and, in some instances, display important differences with comparable Rh₂- and Fe-supported reactions.

Solvent- and transition metal-free amide synthesis from phenyl esters and aryl amines

A general, economical, and environmentally friendly method of amide synthesis from phenyl esters and aryl amines was developed. This new method has significant advantages compared to previously reported palladium-catalyzed approaches. The reaction is performed transition metal- and solvent-free, using a cheap and environmentally benign base, NaH. This approach enabled us to obtain target amides in high yields with high atom economy.

A Highly Active Ylide-Functionalized Phosphine for Palladium-Catalyzed Aminations of Aryl Chlorides

Ylide-functionalized phosphine ligands (YPhos) were rationally designed to fit the requirements of Buchwald-Hartwig aminations at room temperature. This ligand class combines a strong electron-donating ability comparable to NHC ligands with high steric demand similar to biaryl phosphines. The active Pd species are stabilized by agostic C-H⋅⋅⋅Pd rather than by Pd-arene interactions. The practical advantage of YPhos ligands arises from their easy and scalable synthesis from widely available, inexpensive starting materials. Benchmark studies showed that YPhos-Pd complexes are superior to the best-known phosphine ligands in room-temperature aminations of aryl chlorides. The utility of the catalysts was demonstrated by the synthesis of various arylamines in high yields within short reaction times.

Facile synthesis of biarylmethanes and tetrasubstituted arenes via a base-mediated [3 + 3] benzannulation reaction of Morita–Baylis–Hillman adducts and unsaturated sulfones

A regioselective DBU-mediated [3 + 3] benzannulation reaction of 1,3-bis-sulfonyl propenes and Morita–Baylis–Hillman (MBH) bromides to afford bis-sulfonyl biarylmethanes/arenes is described.

Synthesis, structural properties and reactivity of ruthenocene-based pincer Pd(ii) tetrahydroborate

Non-covalent interactions determine the structure, crystal packing and reactivity of isolated ruthenocene-based pincer Pd(ii) complexes. Bifurcate dihydrogen-bonded complexes are active intermediates of tetrahydroborate alcoholysis.

Synthesis ofmeta-substituted anilinesviaa three-component reaction of acetone, amines, and 1,3-diketones

A facilede novosynthesis ofmeta-substituted arylamines based on three-component cyclo-condensation/aromatization ofin situgenerated imines with 1,3-diketones is described.

Rigid hindered N-heterocyclic carbene palladium precatalysts: synthesis, characterization and catalytic amination

Rigid hindered N-heterocyclic carbene palladium complexes have been developed and exhibited high activities for a variety of (hetero)aryl chlorides with (hetero)anilines and amines under aerobic conditions.

Nickel-catalyzed reductive defunctionalization of esters in the absence of an external reductant: activation of C–O bonds

The nickel-catalyzed reductive cleavage of esters in the absence of an external reductant, which involves the cleavage of an inert acyl C–O bond in O-alkyl esters is reported.

Nitrogen-doped heptazethrene and octazethrene diradicaloids

Nitrogen-doped heptazethrene and octazethrene diradicaloids were synthesized. The N-aryl dications show larger diradical character and enhanced stability than the parent ones.

Mixed er-NHC/phosphine Pd(ii) complexes and their catalytic activity in the Buchwald–Hartwig reaction under solvent-free conditions

A single catalyst for solvent-free Buchwald–Hartwig amination with both primary and secondary amines.

N-Arylation of ferrocenyl 2,4-thiazolidinedione conjugatesviaa copper-catalysed Chan–Lam cross coupling reaction with aryl boronic acids and their optoelectronic properties

Copper catalysed Chan–LamN-arylation of ferrocenyl 2,4-thiazolidinedione conjugates is described.

Iodine-catalyzed synthesis of N,N′-diaryl-o-phenylenediamines from cyclohexanones and anilines using DMSO and O2 as oxidants

An I₂/DMSO system has been successfully applied to synthesize N,N′-diaryl-o-phenylenediamines from cyclohexanones for the first time.