Tetrasubstituted Imidazoles Research Articles

ChemInform Abstract: A Facile FeCl3/I2‐Catalyzed Aerobic Oxidative Coupling Reaction: Synthesis of Tetrasubstituted Imidazoles from Amidines and Chalcones.

A facile and efficient route for the synthesis of tetrasubstituted imidazoles from amidines and chalcones via FeCl3/I2-catalyzed aerobic oxidative coupling has been developed. This new strategy is featured by high regioselectivity and yields, good functional group tolerance, and mild reaction conditions.

ChemInform Abstract: Current Advances in the Synthesis and Biological Potencies of Tri‐ and Tetra‐Substituted 1H‐Imidazoles

AbstractReview: 225 refs.

ChemInform Abstract: Synthesis of Novel Organosiliconsulfur‐Containing Tetrasubstituted Imidazoles Sonocatalyzed by LaxSr1‐xFeyCo1‐yO3 Nanoperovskites.

Abstract13 Tetrasubstituted imidazoles (IV) are prepared under ultrasonic irradiation.

A Facile FeCl3/I2-Catalyzed Aerobic Oxidative Coupling Reaction: Synthesis of Tetrasubstituted Imidazoles from Amidines and Chalcones.

A facile and efficient route for the synthesis of tetrasubstituted imidazoles from amidines and chalcones via FeCl3/I2-catalyzed aerobic oxidative coupling has been developed. This new strategy is featured by high regioselectivity and yields, good functional group tolerance, and mild reaction conditions.

ChemInform Abstract: Multicomponent Synthesis of Substituted and Fused‐Ring Imidazoles via Phospha‐Muenchnone Cycloaddition.

AbstractThe reaction of imines (I) with acyl chlorides (II) and 2‐phenyl‐1,3,2‐benzodioxaphosphole followed by reaction of intermediate phospha‐muenchnones with imines (III) leads to a variety of tetrasubstituted imidazoles (IV).

Current advances in the synthesis and biological potencies of tri- and tetra-substituted 1H-imidazoles.

In this report, we review the current chemistry progress and in particular the synthesis approaches of tri- and tetra-substituted imidazoles.

Synthesis of Novel Organosiliconsulfur-Containing Tetrasubstituted Imidazoles Sonocatalyzed by LaxSr1−xFeyCo1−yO3 Nanoperovskites

The one-pot synthesis of tetrasubstituted imidazoles by use of a series of LaxSr1 − xFeyCo1 − yO3 perovskites as catalysts is described. The La0.8Sr0.2Fe0.34Co0.66O3 nanocatalyst had the greatest activity in the heterogeneous cyclocondensation of an aldehyde, benzil, ammonium acetate, and a primary aromatic amine in water under ultrasonic irradiation. Some of the derivatives generated during this work were utilized as substrates for the synthesis in good yields of novel multifunctional tetrasubstituted imidazoles with Me3Si, C=S, and SH groups, via nucleophilic attack of tris(trimethylsilyl)methyllithium (TsiLi) at the carbon of carbon disulphide.

Aspartic acid as a highly efficient and nontoxic organocatalyst for the one-pot synthesis of tri- and tetrasubstituted imidazoles under solvent-free conditions

Aspartic acid was found to be an efficient organocatalyst for the one-pot synthesis of tri- and tetrasubstituted imidazoles under solvent-free conditions. The remarkable advantages offered by this method are the inexpensive and green catalyst, mild reaction conditions, simple procedures, and excellent yield of products.

Corrigendum to “Tetra-substituted imidazoles as a new class of inhibitors of the p53–MDM2 interaction” [Bioorg. Med. Chem. Lett. 24 (9) (2014) 2110–2114

Corrigendum to “Tetra-substituted imidazoles as a new class of inhibitors of the p53–MDM2 interaction” [Bioorg. Med. Chem. Lett. 24 (9) (2014) 2110–2114

ChemInform Abstract: MCPBA‐Promoted Tandem Michael Addition—Intramolecular Cyclization of 2‐Azido‐β‐amino Esters: Single Pot, Convenient Access to 1,2,4,5‐Tetrasubstituted Imidazoles.

AbstractAttempts upon chromatographic separation of the diastereomeric starting material fail.

Silica coated magnetic NiFe2O4 nanoparticle supported phosphomolybdic acid; synthesis, preparation and its application as a heterogeneous and recyclable catalyst for the one-pot synthesis of tri- and tetra-substituted imidazoles under solvent free conditions

A novel heteropolyacid supported on silica coated nickel ferrite nanoparticles (NFS–PMA) was synthesized and used as a green catalyst for one-pot syntheses of tri/tetra-substituted imidazoles. The catalyst could be recycled and reused through application of a magnetic field.

Tetra-substituted pyridinylimidazoles as dual inhibitors of p38α mitogen-activated protein kinase and c-Jun N-terminal kinase 3 for potential treatment of neurodegenerative diseases.

Tetra-substituted imidazoles were designed as dual inhibitors of c-Jun N-terminal kinase (JNK) 3 and p38α mitogen-activated protein (MAP) kinase. A library of 45 derivatives was prepared and evaluated in a kinase activity assay for their ability to inhibit both kinases, JNK3 and p38α MAP kinase. Dual inhibitors with IC50 values down to the low double-digit nanomolar range at both enzymes were identified. The best balanced dual JNK3/p38α MAP kinase inhibitors are 6m (IC50: JNK3, 18 nM; p38α, 30 nM) and 14d (IC50: JNK3, 26 nM; p38α, 34 nM) featuring both excellent solubility and metabolic stability. They may serve as useful tool compounds for preclinical proof-of-principle studies in order to validate the synergistic role of both kinases in the progression of Huntington's disease.

A photochemical one-pot three-component synthesis of tetrasubstituted imidazoles.

Tetrasubstituted imidazoles can be formed in a photochemical one-pot synthesis from aldehydes, α-aminonitriles, and isoxazoles. Condensation of the first two components produces α-(alkylideneamino)nitriles which react under basic conditions with the acylazirines formed in situ by photochemical ring transformation of the isoxazole component. This process includes an unusual cleavage of the C(2)-C(3) bond of the acylazirine. The reaction mechanism was studied by DFT calculations.

Application of a Keplerate type giant nanoporous isopolyoxomolybdate as a reusable catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles

The Keplerate-type giant nanoporous isopolyoxomolybdate (NH4)42[MoVI72MoV60O372-(CH3COO)30(H2O)72], denoted {Mo132}, has been used as a catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles by the one-pot, four-component thermal reaction of benzil with aromatic aldehydes, primary amines, and ammonium acetate under solvent-free conditions. The catalyst was prepared according to a previously published literature procedure using inexpensive and readily available starting materials, and subsequently characterized by FT-IR, UV and X-ray diffraction spectroscopy, as well as microanalysis. The results showed that {Mo132} exhibited high catalytic activity towards the synthesis of 1,2,4,5-tetrasubstituted imidazoles, with the desired products being formed in good to high yields. Furthermore, the catalyst was recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of 1,2,4,5-tetrasubstituted imidazoles provides rapid access to the desired compounds following a simple work-up procedure, and avoids the use of harmful organic solvents. This method therefore represents a significant improvement over the methods currently available for the synthesis of tetrasubstituted imidazoles.

Synthesis of novel organosilicon compounds possessing highly substituted imidazole core catalyzed by antimony trioxide

A general synthetic route for the exclusive preparation of tetrasubstituted imidazoles, possessing benzylic methyl groups has been developed using Sb2O3 via solvent-free, one-pot reaction conditions. Detailed results from our investigation on the bromination of the benzylic methyl groups of imidazoles are described. The products generated during this study were utilized as substrates for the synthesis of organosilicon-containing imidazoles. Synthesis of tris(triorganosilyl)methylimidazole derivatives was carried out using organolithium reagents (RSiMe2)3CLi, (R= H, Me, Ph) prepared via metalation of (RSiMe2)3CH with lithiumdiisopropylamide or methyllithium in THF, in excellent yields. (RSiMe2)3CLi, (R= Me, Ph) were treated with formylated imidazole to afford imidazole containing 2,2-bis(organosilyl)ethenyl groups. 2-(4-(2,2-bis(trimethylsilyl)vinyl)phenyl)-1,4,5-triphenyl-1H-imidazole was obtained via Peterson reaction in high yield. However, compound 2-(4-(2,2-bis(dimethyl(phenyl)silyl)vinyl)phenyl)-1,4,5-triphenyl-1H-imidazole was obtained in low yield likely because of the steric hindrance of the (PhSiMe2)3C- group.

Synthesis of 2-aryl-1,1-Bis(Silyl)Alkenes-Containing Tetrasubstituted Imidazoles Catalysed by M–Cu/ZSM-5 (M: Cr, Mn, Co, Ni, V, Zn and Fe) Zeolites-Supported Bimetallic Nanostructures

The one-pot synthesis of tetrasubstituted imidazoles by using a series of M-Cu/ZSM-5 (M: Cr, Mn, Co, Ni, V, Zn and Fe) zeolites-supported bimetallic catalysts was studied. Fe-Cu/ZSM-5 bimetallic oxide catalyst had the highest activity in improving the efficiency of the heterogeneous cyclo-condensation reaction. Some imidazole derivatives terminated by vinylbis(silanes) have been synthesised using (Me3Si)3CLi through the Peterson olefination reaction.

1-(Imidazol-1-yl)-indolizines—two-step synthesis and optical properties

A one-pot process leading to complex aromatic heterocyclic compounds has been designed. Kröhnke methodology has been used to synthesize indolizines bearing an aldimino-substituent at position 1. Further reaction of these compounds with 1,2-diketones and ammonium acetate led to tetra-substituted imidazoles in 5–28% overall yield. The resulting compounds display strong absorption of UV radiation and emission of a blue light accompanied with large Stokes shifts. Replacing the aryl substituents with thiophene at position 3 of the indolizine and position 2 of the imidazole produce a further red shift of the absorption (vs products with substituted benzene rings) as a result of a more planar conformation in the ground state.

MCPBA-Promoted Tandem Michael Addition–Intramolecular Cyclization of 2-Azido-β-amino Esters: Single Pot, Convenient Access to 1,2,4,5-Tetrasubstituted Imidazoles

A simple, single-pot synthesis of tetrasubstituted imidazoles has been developed through the use of MCPBA-promoted tandem Michael addition–intramolecular cyclization of 2-azido-β-amino esters.

ChemInform Abstract: New Conditions for the Effective Synthesis of Tri‐ and Tetrasubstituted Imidazoles Catalyzed by Recyclable Indium(III) Triflate and Magnesium Sulfate Heptahydrate.

AbstractSubstituted imidazole derivatives such as (IV) and (V) are obtained in one‐pot multicomponent reactions under solvent‐free conditions using In(O‐Tf)3 or MgSO4 as highly efficient and recyclable catalysts.

ChemInform Abstract: Ni(II)—Salt Catalyzed Activation of Primary Amine‐sp3Cα—H and Cyclization with 1,2‐Diketone to Tetrasubstituted Imidazoles.

AbstractBenzylic and aliphatic amines can be applied in the reaction requiring different catalysts.