N-aryl Benzamides Research Articles

Supported-Pd catalyzed tandem approach for N-arylbenzamides synthesis

Aryl iodides as dual arylating agent for C-terminal from oxalic acid [(CO2H)2] and N-terminal from sodium azide (NaN3) for N-aryl benzamides (Ar-CO-NH-Ar) synthesis is a rare invention which has been attempted successfully under this study. A single step tandem approach for the synthesis of N-aryl benzamides has been developed through bifunctional transformation of aryl iodides with in-situ CO from (CO2H)2 and NaN3 following two different pathways of carbonylation and azidation. The polystyrene supported palladium (Pd@PS) catalyst was found to be well compatible to perform the domino-reaction in a double layer vial (DLV) system under base, ligand and additive-free conditions. Moreover, the same approach was further extended with aryl azides for unsymmetric N-aryl benzamides (Ar-CO-NH-Ar') synthesis. Furthermore, the DFT studies were also performed to support the proposed mechanism.

Mapping the Azolog Space Enables the Optical Control of New Biological Targets.

Photopharmacology relies on molecules that change their biological activity upon irradiation. Many of these are derived from known drugs by replacing their core with an isosteric azobenzene photoswitch (azologization). The question is how many of the known bioactive ligands could be addressed in such a way. Here, we systematically assess the space of molecules amenable to azologization from databases of bioactive molecules (DrugBank, PDB, CHEMBL) and the Cambridge Structural Database. Shape similarity scoring functions (3DAPfp) and analyses of dihedral angles are employed to quantify the structural homology between a bioactive molecule and the cis or trans isomer of its corresponding azolog (“azoster”) and assess which isomer is likely to be active. Our analysis suggests that a very large number of bioactive ligands (>40 000) is amenable to azologization and that many new biological targets could be addressed with photopharmacology. N-Aryl benzamides, 1,2-diarylethanes, and benzyl phenyl ethers are particularly suited for this approach, while benzylanilines and sulfonamides appear to be less well-matched. On the basis of our analysis, the majority of azosters are expected to be active in their trans form. The broad applicability of our approach is demonstrated with photoswitches that target a nuclear hormone receptor (RAR) and a lipid processing enzyme (LTA4 hydrolase).

Synthesis, structural, optical and thermal properties of N-methyl–N-aryl benzamide organic single crystals grown by a slow evaporation technique

The organic materials, N-methyl–N-aryl benzamides were synthesized from benzoylation of N-methyl-4-nitrobenzenamine (MNBA) using suitably substituted benzoyl chlorides. The products were purified by recrystallization and their single crystal were grown by a slow evaporation technique. The crystals were characterized by FTIR, UV–Vis–NIR, 1H &13C NMR, and single & powder X-ray diffraction. Thermal stability of the crystals was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Dielectric and NLO properties of MNPB, FMNPB and MMNPB crystals were studied. The second harmonic generation (SHG) has been confirmed by the Kurtz powder test for all these crystals and the SHG efficiency of MMNPB crystal was found to be 2.25 times higher than that of KDP crystal.

Efficient Method for the Synthesis of Benzamides from Benzoic Acids and Aryl Isothiocyanates using K2 HPO4

An efficient and convenient cross-coupling method for the synthesis of N-aryl benzamides from benzoic acids and aryl isothiocyanates has been developed. K2HPO4 can be used as an efficient reagent for the synthesis of N-aryl benzamides. The method is applicable to a wide variety of benzoic acids and aryl isothiocyanates.

ChemInform Abstract: Transition‐Metal‐Catalyzed Direct Addition of Aryl C—H Bonds to Unsaturated Electrophiles

AbstractReview: [37 refs.

Transition-Metal-Catalyzed Direct Addition of Aryl C-H Bonds to Unsaturated Electrophiles.

The direct addition of Csp(2) -H bonds onto polar C=C, C=O, and C=N bonds is both synthetically and mechanistically important, because using aromatic C-H substrates in place of organometallic reagents provides a more direct and atom-economical alternative to many important compounds without the pre-generation of organometallic compounds from stoichiometric halides and the unavoidable generation of stoichiometric metal halide waste. In this account, we summarize our contributions to the transition-metal-catalyzed addition of aromatic C-H bonds to polar C=C, C=O, and C=N bonds via directing-group-assisted regiospecific reactions. These synthetic methods provide efficient access to benzylic alcohols, alkylbenzenes, 3-substituted phthalides, N-substituted phthalimides, N-aryl benzamides, and indene derivatives from commercially available reagents. It is worth noting that valuable heterocycles such as 3-substituted phthalides and N-substituted phthalimides can be obtained in one step by this approach.

ChemInform Abstract: A Convenient Synthesis of N‐Aryl Benzamides by Rhodium‐Catalyzed ortho‐Amidation and Decarboxylation of Benzoic Acids.

The rhodium-catalyzed amidation of substituted benzoic acids with isocyanates by directed CH functionalization followed by decarboxylation to afford the corresponding N-aryl benzamides is demonstrated, in which the carboxylate serves as a unique, removable directing group. Notably, less common meta-substituted N-aryl benzamides are generated readily from more accessible para- or ortho-substituted groups by employing this strategy.

Ru(II)-catalyzed ortho-amidation and decarboxylation of aromatic acids: a versatile route to meta-substituted N-aryl benzamides

Carboxylate as a promising and valuable directing group has attracted a great deal of attention. However, employing it as a traceless direction group has rarely been reported. We developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C-H functionalization followed by decarboxylation to afford the corresponding meta- substituted N -aryl benzamides, in which the carboxylate serves as a unique, removable directing group. Notably, this protocol can provide an efficient alternative to access meta -substituted N -aryl benzamides, which are much more difficult to prepare than ortho -substituted analogues.

Synthesis of N-aryl benzamides containing pharmacophoric tyrosine kinase inhibitor fragments

New N-aryl 4-(arylaminomethyl)benzamides containing pharmacophoric heterocyclic fragments have been synthesized from 2-arylaminopyrimidine, 1-methylpiperazine, and morpholine derivatives and substituted benzoic acids.

A convenient synthesis of N-aryl benzamides by rhodium-catalyzed ortho-amidation and decarboxylation of benzoic acids.

The rhodium-catalyzed amidation of substituted benzoic acids with isocyanates by directed CH functionalization followed by decarboxylation to afford the corresponding N-aryl benzamides is demonstrated, in which the carboxylate serves as a unique, removable directing group. Notably, less common meta-substituted N-aryl benzamides are generated readily from more accessible para- or ortho-substituted groups by employing this strategy.

Synthesis of novel substituted N-aryl benzamides as hA3G stabilizers and their inhibitory activities against hepatitis C virus replication

A series of novel amino-substituted N-aryl benzamide analogs were synthesized and evaluated for their ability to inhibit hepatitis C virus (HCV) replication in acutely infected Huh7.5 cells. Most of the substituted N-aryl benzamide compounds showed convincing anti-HCV activities. Compounds 1f, 1g and 4c exhibited potent anti-replicative activity at low micromolar levels (IC50=1.0–2.0μM) with selective indices (SI) greater than 40. Mechanistic analysis indicated that the active compounds increased intracellular hA3G protein levels and inhibited HCV replication in a dose-dependent manner. The results demonstrate that this series of substituted N-aryl benzamide compounds warrant further investigation as inhibitors of HCV replication.

Pd-Catalyzed Intermolecular C–H Amination with Alkylamines

C-H amination of N-aryl benzamides with O-benzoyl hydroxylamines has been achieved with either Pd(II) or Pd(0) catalysts. Furthermore, we demonstrate that secondary amines can be directly used with benzoyl peroxide in a one-pot procedure that proceeds via the in situ generation of the appropriate O-benzoyl hydroxylamines. This catalytic reaction provides a new disconnection for the convergent synthesis of tertiary and secondary arylalkyl amines starting from benzoic acids.

ChemInform Abstract: DIRECT SYNTHESIS OF N‐ARYL BENZAMIDES BY REDUCTIVE CARBONYLATION OF NITROARENES CATALYZED BY RHODIUM CARBONYLS IN BENZENE

AbstractDie Nitrobenzole (I) werden in Gegenwart von Benzol, Kohlenmonoxid und Rhodiumcarbonyl‐Katalysatoren wie (II) in die Amide (III), die Amine (IV) und in manchen Fällen zusätzlich in die Diarylharnstoffe (V) übergeführt.

DIRECT SYNTHESIS OF N-ARYL BENZAMIDES BY REDUCTIVE CARBONYLATION OF NITROARENES CATALYZED BY RHODIUM CARBONYLS IN BENZENE

Abstract The reactions of nitroarenes, carbon monoxide, and benzene in the presence of Rh4(CO)12 or Rh6(CO)16 give N-aryl benzamides via the reductive carbonylation of nitroarenes and subsequent addition of benzene to the resulting aryl isocyanates.

RHODIUM CARBONYL CLUSTER CATALYZED ADDITION OF ARENES TO DIPHENYLKETENE AND ARYL ISOCYANATES

Abstract Under pressure of carbon monoxide, rhodium carbonyl clusters catalyze a novel addition of benzene and monosubstituted benzenes to diphenylketene and aryl isocyanates to give benzene-adducts, diphenylmethyl arylketone and N-aryl benzamides, respectively.