Accedi

Bibliografie tematiche / N-Heterocyclic carbenes (NHC) complexes / Articoli di riviste

Segui questo link per vedere altri tipi di pubblicazioni sul tema: N-Heterocyclic carbenes (NHC) complexes.

Articoli di riviste sul tema "N-Heterocyclic carbenes (NHC) complexes"

Autore: Grafiati

Pubblicato: 11 gennaio 2025

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili

Scegli il tipo di fonte:

Vedi i top-50 articoli di riviste per l'attività di ricerca sul tema "N-Heterocyclic carbenes (NHC) complexes".

Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.

Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.

Vedi gli articoli di riviste di molte aree scientifiche e compila una bibliografia corretta.

1

Longevial, Jean-François, Mamadou Lo, Aurélien Lebrun, Danielle Laurencin, Sébastien Clément e Sébastien Richeter. "Molecular complexes and main-chain organometallic polymers based on Janus bis(carbenes) fused to metalloporphyrins". Dalton Transactions 49, n. 21 (2020): 7005–14. http://dx.doi.org/10.1039/d0dt00594k.

Testo completo

Abstract (sommario):

Janus bis(N-heterocyclic carbenes) composed of a porphyrin core with two N-heterocyclic carbene (NHC) heads fused to opposite pyrroles were used as bridging ligands for the preparation of metal complexes.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Mokfi, Moloud, Jörg Rust, Christian W. Lehmann e Fabian Mohr. "Facile N9-Alkylation of Xanthine Derivatives and Their Use as Precursors for N-Heterocyclic Carbene Complexes". Molecules 26, n. 12 (17 giugno 2021): 3705. http://dx.doi.org/10.3390/molecules26123705.

Testo completo

Abstract (sommario):

The xanthine-derivatives 1,3,7-trimethylxanthine, 1,3-dimethyl-7-benzylxanthine and 1,3-dimethyl-7-(4-chlorobenzyl)xanthine are readily ethylated at N9 using the cheap alkylating agents ethyl tosylate or diethyl sulfate. The resulting xanthinium tosylate or ethyl sulfate salts can be converted into the corresponding PF6- and chloride salts. The reaction of these xanthinium salts with silver(I) oxide results in the formation of different silver(I) carbene-complexes. In the presence of ammonia, ammine complexes [Ag(NHC)(NH3)]PF6 are formed, whilst with Et2NH, the bis(carbene) salts [Ag(NHC)2]PF6 were isolated. Using the xanthinium chloride salts neutral silver(I) carbenes [Ag(NHC)Cl] were prepared. These silver complexes were used in a variety of transmetallation reactions to give the corresponding gold(I), ruthenium(II) as well as rhodium(I) and rhodium(III) complexes. The compounds were characterized by various spectroscopic methods as well as X-ray diffraction.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Buchspies, Jonathan, Md Mahbubur Rahman e Michal Szostak. "Suzuki–Miyaura Cross-Coupling of Amides Using Well-Defined, Air- and Moisture-Stable Nickel/NHC (NHC = N-Heterocyclic Carbene) Complexes". Catalysts 10, n. 4 (31 marzo 2020): 372. http://dx.doi.org/10.3390/catal10040372.

Testo completo

Abstract (sommario):

In this Special Issue on N-Heterocyclic Carbenes and Their Complexes in Catalysis, we report the first example of Suzuki–Miyaura cross-coupling of amides catalyzed by well-defined, air- and moisture-stable nickel/NHC (NHC = N-heterocyclic carbene) complexes. The selective amide bond N–C(O) activation is achieved by half-sandwich, cyclopentadienyl [CpNi(NHC)Cl] complexes. The following order of reactivity of NHC ligands has been found: IPr > IMes > IPaul ≈ IPr*. Both the neutral and the cationic complexes are efficient catalysts for the Suzuki–Miyaura cross-coupling of amides. Kinetic studies demonstrate that the reactions are complete in < 1 h at 80 °C. Complete selectivity for the cleavage of exocyclic N-acyl bond has been observed under the experimental conditions. Given the utility of nickel catalysis in activating unreactive bonds, we believe that well-defined and bench-stable [CpNi(NHC)Cl] complexes will find broad application in amide bond and related cross-couplings of bench-stable acyl-electrophiles.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Beig, Nosheen, Varsha Goyal, Raakhi Gupta e Raj K. Bansal. "N-Heterocyclic Carbenes–CuI Complexes as Catalysts: A Theoretical Insight". Australian Journal of Chemistry 74, n. 7 (2021): 503. http://dx.doi.org/10.1071/ch20332.

Testo completo

Abstract (sommario):

The electronic structures of N-heterocyclic carbenes (NHC) imidazolinylidene, thiazolinylidene, imidazolylidene, thiazolylidene, and 1,2,4-triazolylidene and their complexes with cuprous halides (CuX, X=Cl, Br, I) were investigated theoretically at the B3LYP/def2-SVP level. In contrast to other NHCs, imidazolylidene and 1,2,4-triazolylidene do not dimerize owing to the negligible coefficient of the vacant p-orbital at the carbene centre in their respective LUMOs. This is further supported by their greater thermodynamic and kinetic stabilities revealed by greater activation free energies and smaller standard free energies for their dimerization. Second-order perturbation interactions in the natural bond orbital (NBO) analysis of the NHCs indicate that six π electrons are delocalized in imidazolylidene, thiazolylidene, and 1,2,4-triazolylidene, conferring aromatic character and thereby enhancing their thermodynamic stability. NBO analysis reveals the existence of effective back bonding from a d orbital of Cu to the NHC, increasing the Wiberg bond index of the C–Cu bond to ~1.5. Owing to the large electronic chemical potential (μ) and high nucleophilicity indices, NHCs are able to transfer their electron density effectively to the cuprous halides having low μ values and high electrophilicity indices to yield stable NHC–CuI complexes. Large values of the Fukui function f(r) at the carbene centre of the NHCs and Cu atom of the NHC–CuI complexes indicate their softness. Imidazolylidene was found to be the softest, rationalizing wide use of this class of NHCs as ligands. The coordination of the NHCs to cuprous halides is either barrierless or has a very low activation free energy barrier. In the A3 reaction wherein NHC–Cu(I) complexes are used as catalyst, the reaction of NHC–CuI with phenylacetylene changes the latter into acetylide accompanied by raising the energy level of its HOMO considerably compared with the level of the uncomplexed alkyne, making its reaction with benzaldehyde barrierless.

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Savka, Roman, Sabine Foro e Herbert Plenio. "Pentiptycene-based concave NHC–metal complexes". Dalton Transactions 45, n. 27 (2016): 11015–24. http://dx.doi.org/10.1039/c6dt01724j.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Qie, Boyu, Ziyi Wang, Jingwei Jiang, Zisheng Zhang, Peter H. Jacobse, Jiaming Lu, Xinheng Li et al. "Synthesis and characterization of low-dimensional N-heterocyclic carbene lattices". Science 384, n. 6698 (24 maggio 2024): 895–901. http://dx.doi.org/10.1126/science.adm9814.

Testo completo

Abstract (sommario):

The covalent interaction of N-heterocyclic carbenes (NHCs) with transition metal atoms gives rise to distinctive frontier molecular orbitals (FMOs). These emergent electronic states have spurred the widespread adoption of NHC ligands in chemical catalysis and functional materials. Although formation of carbene-metal complexes in self-assembled monolayers on surfaces has been explored, design and electronic structure characterization of extended low-dimensional NHC-metal lattices remains elusive. Here we demonstrate a modular approach to engineering one-dimensional (1D) metal-organic chains and two-dimensional (2D) Kagome lattices using the FMOs of NHC–Au–NHC junctions to create low-dimensional molecular networks exhibiting intrinsic metallicity. Scanning tunneling spectroscopy and first-principles density functional theory reveal the contribution of C–Au–C π-bonding states to dispersive bands that imbue 1D- and 2D-NHC lattices with exceptionally small work functions.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Nonnenmacher, Michael, Dominik M. Buck e Doris Kunz. "Experimental and theoretical investigations on the high-electron donor character of pyrido-annelated N-heterocyclic carbenes". Beilstein Journal of Organic Chemistry 12 (23 agosto 2016): 1884–96. http://dx.doi.org/10.3762/bjoc.12.178.

Testo completo

Abstract (sommario):

Rh(CO)2Cl(NHC) complexes of dipyrido-annelated N-heterocyclic carbenes were prepared. From the C–H coupling constant of the respective imidazolium salts and the N–C–N angle of the N-heterocyclic carbene (NHC), a weaker σ-donor character than that of typical unsaturated NHCs is expected. However, the IR stretching frequencies of their Rh(CO)2Cl complexes suggest an electron-donor character even stronger than that of saturated NHCs. We ascribe this to the extremely weak π-acceptor character of the dipyrido-annelated NHCs caused by the conjugated 14 πe− system that thus allows for an enhanced Rh–CO backbonding. This extremely low π-acceptor ability is also corroborated by the 77Se NMR chemical shift of −55.8 ppm for the respective selenourea, the lowest value ever measured for imidazole derived selenoureas. DFT-calculations of the free carbene confirm the low σ-donor character by the fact that the σ-orbital of the carbene is the HOMO−1 that lies 0.58 eV below the HOMO which is located at the π-system. Natural population analysis reveals the lowest occupation of the pπ-orbital for the saturated carbene carbon atom and the highest for the pyrido-annelated carbene. Going from the free carbene to the Rh(CO)2Cl(NHC) complexes, the increase in occupancy of the complete π-system of the carbene ligand upon coordination is lowest for the pyrido-annelated carbene and highest for the saturated carbene.

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Beig, Nosheen, Varsha Goyal e Raj Kumar Bansal. "Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review". Beilstein Journal of Organic Chemistry 19 (20 settembre 2023): 1408–42. http://dx.doi.org/10.3762/bjoc.19.102.

Testo completo

Abstract (sommario):

N-Heterocyclic carbenes (NHCs) are a special type of carbenes in which the carbene carbon atom is part of the nitrogen heterocyclic ring. Due to the simplicity of their synthesis and the modularity of their stereoelectronic properties, NHCs have unquestionably emerged as one of the most fascinating and well-known species in chemical science. The remarkable stability of NHCs can be attributed to both kinetic as well as thermodynamic effects caused by its structural features. NHCs constitute a well-established class of new ligands in organometallic chemistry. Although initially NHCs were regarded as pure σ-donor ligands, later experimental and theoretical studies established the presence of a significant back donation from the d-orbital of the metal to the π* orbital of the NHC. Over the last two decades, NHC–metal complexes have been extensively used as efficient catalysts in different types of organic reactions. Of these, NHC–Cu(I) complexes found prominence for various reasons, such as ease of preparation, possibility of structural diversity, low cost, and versatile applications. This article overviews applications of NHC–Cu(I) complexes as catalysts in organic synthesis over the last 12 years, which include hydrosilylation reactions, conjugate addition, [3 + 2] cycloaddition, A3 reaction, boration and hydroboration, N–H and C(sp2)–H carboxylation, C(sp2)–H alkenylation and allylation, C(sp2)–H arylation, C(sp2)–H amidation, and C(sp2)–H thiolation. Preceding the section of applications, a brief description of the structure of NHCs, nature of NHC–metal bond, and methods of preparation of NHC–Cu complexes is provided.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Ali, Hanan El-Sharkawy. "Bis-carbene metallic compounds: synthesis of imidazoline derivatives via cycloaddition reaction of isocyanides based on amidines". Journal of Scientific and Innovative Research 6, n. 2 (30 giugno 2017): 50–54. http://dx.doi.org/10.31254/jsir.2017.6202.

Testo completo

Abstract (sommario):

In an effort to develop new classes of NHC (N-heterocyclic carbenes) complexes, two imidazoline-anchored ligand systems have been synthesized. The process is superior owing to two approaches: (i) a new synthesized phase transfer catalyst, namely, 1,1'-benzene-1,4-diyldipyridinium dibromide (BDPDB) used to catalyze the phase-transfer Hoffmann reaction of two structurally varied amines, dodecylamine and 1-amino-9,10- anthraquinone. The reaction successfully gave the corresponding isocyanides that display the highest reactivity in reasonable to good yields. (ii) A cycloaddition-rearrangement reaction between amidines and isocyanides gives easy access to a diverse range of highly substituted 5- and 2-imidazolines. Furthermore, imidazoline based bis-NHC (N-heterocyclic carbenes) precursors were prepared and complexed to copper cation (5-Z and 2-Z, Chart 1).

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Leitão, Maria Inês P. S., Giulia Francescato, Clara S. B. Gomes e Ana Petronilho. "Synthesis of Platinum(II) N-Heterocyclic Carbenes Based on Adenosine". Molecules 26, n. 17 (4 settembre 2021): 5384. http://dx.doi.org/10.3390/molecules26175384.

Testo completo

Abstract (sommario):

Organometallic derivatization of nucleosides is a highly promising strategy for the improvement of the therapeutic profile of nucleosides. Herein, a methodology for the synthesis of metalated adenosine with a deprotected ribose moiety is described. Platinum(II) N-heterocyclic carbene complexes based on adenosine were synthesized, namely N-heterocyclic carbenes bearing a protected and unprotected ribose ring. Reaction of the 8-bromo-2′,3′,5′-tri-O-acetyladenosine with Pt(PPh3)4 by C8−Br oxidative addition yielded complex 1, with a PtII centre bonded to C-8 and an unprotonated N7. Complex 1 reacted at N7 with HBF4 or methyl iodide, yielding protic carbene 2 or methyl carbene 3, respectively. Deprotection of 1 to yield 4 was achieved with NH4OH. Deprotected compound 4 reacted at N7 with HCl solutions to yield protic NHC 5 or with methyl iodide yielding methyl carbene 6. Protic N-heterocyclic carbene 5 is not stable in DMSO solutions leading to the formation of compound 7, in which a bromide was replaced by chloride. The cis-influence of complexes 1–7 was examined by 31P{1H} and 195Pt NMR. Complexes 2, 3, 5, 6 and 7 induce a decrease of 1JPt,P of more than 300 Hz, as result of the higher cis-influence of the N-heterocyclic carbene when compared to the azolato ligand in 1 and 4.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Urbina-Blanco, César A., Xavier Bantreil, Hervé Clavier, Alexandra M. Z. Slawin e Steven P. Nolan. "Backbone tuning in indenylidene–ruthenium complexes bearing an unsaturated N-heterocyclic carbene". Beilstein Journal of Organic Chemistry 6 (23 novembre 2010): 1120–26. http://dx.doi.org/10.3762/bjoc.6.128.

Testo completo

Abstract (sommario):

The steric and electronic influence of backbone substitution in IMes-based (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) N-heterocyclic carbenes (NHC) was probed by synthesizing the [RhCl(CO)2(NHC)] series of complexes to quantify experimentally the Tolman electronic parameter (electronic) and the percent buried volume (%V bur, steric) parameters. The corresponding ruthenium–indenylidene complexes were also synthesized and tested in benchmark metathesis transformations to establish possible correlations between reactivity and NHC electronic and steric parameters.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Tialiou, Alexia, Jiamin Chin, Bernhard K. Keppler e Michael R. Reithofer. "Current Developments of N-Heterocyclic Carbene Au(I)/Au(III) Complexes toward Cancer Treatment". Biomedicines 10, n. 6 (15 giugno 2022): 1417. http://dx.doi.org/10.3390/biomedicines10061417.

Testo completo

Abstract (sommario):

Since their first discovery, N-heterocyclic carbenes have had a significant impact on organometallic chemistry. Due to their nature as strong σ-donor and π-acceptor ligands, they are exceptionally well suited to stabilize Au(I) and Au(III) complexes in biological environments. Over the last decade, the development of rationally designed NHCAu(I/III) complexes to specifically target DNA has led to a new “gold rush” in bioinorganic chemistry. This review aims to summarize the latest advances of NHCAu(I/III) complexes that are able to interact with DNA. Furthermore, the latest advancements on acyclic diamino carbene gold complexes with anticancer activity are presented as these typically overlooked NHC alternatives offer great additional design possibilities in the toolbox of carbene-stabilized gold complexes for targeted therapy.

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Lv, Gaochao, Liubin Guo, Ling Qiu, Hui Yang, Tengfei Wang, Hong Liu e Jianguo Lin. "Lipophilicity-dependent ruthenium N-heterocyclic carbene complexes as potential anticancer agents". Dalton Transactions 44, n. 16 (2015): 7324–31. http://dx.doi.org/10.1039/c5dt00169b.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Bensalah, Donia, Nevin Gurbuz, Ismail Özdemir, Rafik Gatri, Lamjed Mansour e Naceur Hamdi. "Synthesis, Characterization, Antimicrobial Properties, and Antioxidant Activities of Silver-N-Heterocyclic Carbene Complexes". Bioinorganic Chemistry and Applications 2023 (26 maggio 2023): 1–15. http://dx.doi.org/10.1155/2023/3066299.

Testo completo

Abstract (sommario):

The emergence of antimicrobial resistance has become a major handicap in the fight against bacterial infections, prompting researchers to develop new, more effective, and multimodal alternatives. Silver and its complexes have long been used as antimicrobial agents in medicine because of their lack of resistance to silver, their low potency at low concentrations, and their low toxicity compared to most commonly used antibiotics. N-Heterocyclic carbenes (NHCs) are widely used for coordination of transition metals, mainly in catalytic chemistry. In this study, several N-alkylated benzimidazolium salts 2a–j were synthesized. Then, the N-heterocyclic carbene (NHC) precursor was treated with Ag2O to give silver (I) NHC complexes (3a–j) at room temperature in dichloromethane for 48 h. Ten new silver-NHC complexes were fully characterized by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and LC-MSMS (for complexes) techniques. The antibacterial and antioxidant activities of salt 2 and its silver complex 3 were evaluated. All of these complexes were more effective against bacterial strains than comparable ligands. With MIC values ranging from 6.25 to 100 g/ml, the Ag-NHC complex effectively showed strong antibacterial activity. Antioxidant activity was also tested using conventional techniques, such as 2, 2-diphenyl-1-picrylhydrazine (DPPH) and hydrogen peroxide scavenging assays. In DPPH and ABTS experiments, compounds 3a, 3b, 3c, 3e, 3g, and 3i showed significant clearance.

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Hille, Claudia, e Fritz E. Kühn. "Cationic rhenium complexes ligated with N-heterocyclic carbenes – an overview". Dalton Transactions 45, n. 1 (2016): 15–31. http://dx.doi.org/10.1039/c5dt03641k.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Prencipe, Filippo, Anna Zanfardino, Michela Di Napoli, Filomena Rossi, Stefano D’Errico, Gennaro Piccialli, Giuseppe Felice Mangiatordi et al. "Silver (I) N-Heterocyclic Carbene Complexes: A Winning and Broad Spectrum of Antimicrobial Properties". International Journal of Molecular Sciences 22, n. 5 (2 marzo 2021): 2497. http://dx.doi.org/10.3390/ijms22052497.

Testo completo

Abstract (sommario):

The evolution of antibacterial resistance has arisen as the main downside in fighting bacterial infections pushing researchers to develop novel, more potent and multimodal alternative drugs.Silver and its complexes have long been used as antimicrobial agents in medicine due to the lack of silver resistance and the effectiveness at low concentration as well as to their low toxicities compared to the most commonly used antibiotics. N-Heterocyclic Carbenes (NHCs) have been extensively employed to coordinate transition metals mainly for catalytic chemistry. However, more recently, NHC ligands have been applied as carrier molecules for metals in anticancer applications. In the present study we selected from literature two NHC-carbene based on acridinescaffoldand detailed nonclassicalpyrazole derived mono NHC-Ag neutral and bis NHC-Ag cationic complexes. Their inhibitor effect on bacterial strains Gram-negative and positivewas evaluated. Imidazolium NHC silver complex containing the acridine chromophore showed effectiveness at extremely low MIC values. Although pyrazole NHC silver complexes are less active than the acridine NHC-silver, they represent the first example of this class of compounds with antimicrobial properties. Moreover all complexesare not toxic and they show not significant activity againstmammalian cells (Hek lines) after 4 and 24 h. Based on our experimental evidence, we are confident that this promising class of complexes could represent a valuable starting point for developing candidates for the treatment of bacterial infections, delivering great effectiveness and avoiding the development of resistance mechanisms.

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Kiefer, Claude, Sebastian Bestgen, Michael T. Gamer, Sergei Lebedkin, Manfred M. Kappes e Peter W. Roesky. "Alkynyl-functionalized gold NHC complexes and their coinage metal clusters". Dalton Transactions 44, n. 30 (2015): 13662–70. http://dx.doi.org/10.1039/c5dt02228b.

Testo completo

Abstract (sommario):

Phenylpropynyl-functionalized N-heterocyclic carbenes as ligands for the synthesis of heterometallic hexanuclear coinagemetal clusters which exhibit mixed metallophillic interactions and intense white photoluminescence at low temperature.

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Sun, Hongsui, Xiao-Yan Yu, Paolo Marcazzan, Brian O. Patrick e Brian R. James. "Rhodium(I)–(N-heterocyclic carbene)–diphosphine complexes". Canadian Journal of Chemistry 87, n. 9 (settembre 2009): 1248–54. http://dx.doi.org/10.1139/v09-118.

Testo completo

Abstract (sommario):

Reactions of [RhCl(COE)(IPr)]2 (1) and [RhCl(COE)(IMes)]2 (2) (COE = cyclooctene; IPr = N,N′-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene; IMes = N,N′-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) with the diphosphines Ph2P(CH2)nPPh2 and 1,2-bis(diphenylphosphino)benzene (dppbz) give the N-heterocyclic carbene (NHC) – diphosphine – rhodium(I) complexes: RhCl(NHC)[Ph2P(CH2)nPPh2] [NHC = IPr, n = 1 (3); NHC = IMes, n = 1 (4); NHC = IPr, n = 2 (5); NHC = IMes, n = 2 (6); NHC = IPr, n = 4 (7); NHC = IMes, n = 4 (8)] and RhCl(NHC)(dppbz) [NHC = IPr (9); NHC = IMes (10)]. All the complexes are characterized by 1H, 31P{1H}, and 13C{1H} NMR spectroscopy, elemental analysis, and mass spectrometry. Complexes 3, 7, and 9 are also characterized crystallographically. In benzene solution, the complexes decompose in the presence of O2 with formation of the diphosphine dioxide, whereas reaction with CO leads to replacement of the NHC ligand to give known carbonyl–diphosphine complexes.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Ruamps, Mirko, Stéphanie Bastin, Lionel Rechignat, Alix Sournia-Saquet, Laure Vendier, Noël Lugan, Jean-Marie Mouesca, Dmitry A. Valyaev, Vincent Maurel e Vincent César. "Redox-Switchable Behavior of Transition-Metal Complexes Supported by Amino-Decorated N-Heterocyclic Carbenes". Molecules 27, n. 12 (11 giugno 2022): 3776. http://dx.doi.org/10.3390/molecules27123776.

Testo completo

Abstract (sommario):

The coordination chemistry of the N-heterocyclic carbene ligand IMes(NMe2)2, derived from the well-known IMes ligand by substitution of the carbenic heterocycle with two dimethylamino groups, was investigated with d6 [Mn(I), Fe(II)], d8 [Rh(I)], and d10 [Cu(I)] transition-metal centers. The redox behavior of the resulting organometallic complexes was studied through a combined experimental/theoretical study, involving electrochemistry, EPR spectroscopy, and DFT calculations. While the complexes [CuCl(IMes(NMe2)2)], [RhCl(COD)(IMes(NMe2)2)], and [FeCp(CO)2 (IMes(NMe2)2)](BF4) exhibit two oxidation waves, the first oxidation wave is fully reversible but only for the first complex the second oxidation wave is reversible. The mono-oxidation event for these complexes occurs on the NHC ligand, with a spin density mainly located on the diaminoethylene NHC-backbone, and has a dramatic effect on the donating properties of the NHC ligand. Conversely, as the Mn(I) center in the complex [MnCp(CO)2 ((IMes(NMe2)2)] is easily oxidizable, the latter complex is first oxidized on the metal center to form the corresponding cationic Mn(II) complex, and the NHC ligand is oxidized in a second reversible oxidation wave.

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Neshat, Abdollah, Piero Mastrorilli e Ali Mousavizadeh Mobarakeh. "Recent Advances in Catalysis Involving Bidentate N-Heterocyclic Carbene Ligands". Molecules 27, n. 1 (24 dicembre 2021): 95. http://dx.doi.org/10.3390/molecules27010095.

Testo completo

Abstract (sommario):

Since the discovery of persistent carbenes by the isolation of 1,3-di-l-adamantylimidazol-2-ylidene by Arduengo and coworkers, we witnessed a fast growth in the design and applications of this class of ligands and their metal complexes. Modular synthesis and ease of electronic and steric adjustability made this class of sigma donors highly popular among chemists. While the nature of the metal-carbon bond in transition metal complexes bearing N-heterocyclic carbenes (NHCs) is predominantly considered to be neutral sigma or dative bonds, the strength of the bond is highly dependent on the energy match between the highest occupied molecular orbital (HOMO) of the NHC ligand and that of the metal ion. Because of their versatility, the coordination chemistry of NHC ligands with was explored with almost all transition metal ions. Other than the transition metals, NHCs are also capable of establishing a chemical bond with the main group elements. The advances in the catalytic applications of the NHC ligands linked with a second tether are discussed. For clarity, more frequently targeted catalytic reactions are considered first. Carbon–carbon coupling reactions, transfer hydrogenation of alkenes and carbonyl compounds, ketone hydrosilylation, and chiral catalysis are among highly popular reactions. Areas where the efficacy of the NHC based catalytic systems were explored to a lesser extent include CO2 reduction, C-H borylation, alkyl amination, and hydroamination reactions. Furthermore, the synthesis and applications of transition metal complexes are covered.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Khalili Najafabadi, Bahareh, e John F. Corrigan. "Silylphosphido complexes of gold(I) coordinated with NHC ligands". Canadian Journal of Chemistry 94, n. 7 (luglio 2016): 593–98. http://dx.doi.org/10.1139/cjc-2016-0096.

Testo completo

Abstract (sommario):

The N-heterocyclic carbenes IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and iPr2-bimy (iPr2-bimy = 1,3-di-isopropylbenzimidazole-2-ylidene) were utilized as a basis for the preparation of four gold–silylphosphido complexes: [(IPr)AuP(Ph)SiMe3] (1), [(IPr)AuP(SiMe3)2] (2), [(iPr2-bimy)AuP(Ph)SiMe3] (3), and [(iPr2-bimy)AuP(SiMe3)2] (4). These complexes represent rare examples of terminally bonded Au–PR2 and the first examples where phosphorus retains reactive P-SiMe3 moieties. The reactivity of the P–Si bonds in 1 and 3 was explored via the addition of PhC(O)Cl. The products of these reactions were the formation of the phosphido-bridged [(IPrAu)2(μ-PPhC(O)Ph)][AuCl2] (5) and, in the case of the smaller N-heterocyclic carbenes, the tertiary phosphine PPh(C(O)Ph)2 (6) was isolated together with the known gold complex [(iPr2-bimy)AuCl]. Both reactions proceed via the elimination of ClSiMe3.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Liu, Ming, Jan C. Namyslo, Martin Nieger, Mika Polamo e Andreas Schmidt. "From betaines to anionic N-heterocyclic carbenes. Borane, gold, rhodium, and nickel complexes starting from an imidazoliumphenolate and its carbene tautomer". Beilstein Journal of Organic Chemistry 12 (8 dicembre 2016): 2673–81. http://dx.doi.org/10.3762/bjoc.12.264.

Testo completo

Abstract (sommario):

The mesomeric betaine imidazolium-1-ylphenolate forms a borane adduct with tris(pentafluorophenyl)borane by coordination with the phenolate oxygen, whereas its NHC tautomer 1-(2-phenol)imidazol-2-ylidene reacts with (triphenylphosphine)gold(I) chloride to give the cationic NHC complex [Au(NHC)2][Cl] by coordination with the carbene carbon atom. The anionic N-heterocyclic carbene 1-(2-phenolate)imidazol-2-ylidene gives the complexes [K][Au(NHC−)2], [Rh(NHC−)3] and [Ni(NHC−)2], respectively. Results of four single crystal analyses are presented.

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Wu, Melissa M., Arran M. Gill, Lu Yunpeng, Li Yongxin, Rakesh Ganguly, Laura Falivene e Felipe García. "Aryl-NHC-group 13 trimethyl complexes: structural, stability and bonding insights". Dalton Transactions 46, n. 3 (2017): 854–64. http://dx.doi.org/10.1039/c6dt04448d.

Testo completo

Abstract (sommario):

Treatment of aromatic N-substituted N-heterocyclic carbenes (NHCs) with trimethylgallium and -indium yielded the new Lewis acid–base adducts (as shown in the Figure). The steric and electronic factors affecting the stability of these complexes were quantified using percent buried volume, topographic steric maps and theoretical studies.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Zhang, Shu, Wen-Chao Zhang, Dan-Dan Shang, Zhi-Qian Zhang e Yi-Xian Wu. "Ethylene/propylene copolymerization catalyzed by vanadium complexes containing N-heterocyclic carbenes". Dalton Transactions 44, n. 34 (2015): 15264–70. http://dx.doi.org/10.1039/c5dt00675a.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Crochet, Pascale, e Victorio Cadierno. "Gold Complexes with Hydrophilic N-Heterocyclic Carbene Ligands and Their Contribution to Aqueous-Phase Catalysis". Catalysts 13, n. 2 (17 febbraio 2023): 436. http://dx.doi.org/10.3390/catal13020436.

Testo completo

Abstract (sommario):

N-Heterocyclic carbenes (NHCs) are nowadays one of the most widely employed ligands in organometallic chemistry and homogeneous catalysis due to the inherent stability of the metal-carbene bond and the ease of modification of the backbone as well as the N-wingtips substituents of these ligands. The functionalization of NHCs with hydrophilic groups offers the possibility of using NHC-metal complexes in aqueous catalysis, a hot topic within the Green Chemistry context due to the positive implications associated with the use of water as a reaction medium. In line with the enormous interest aroused by gold complexes in catalysis, significant efforts have been directed in the last years to the design and application of hydrophilic NHC-gold catalysts. This review is aimed to summarize the research in this area. The catalytic applications of water-soluble gold nanoparticles stabilized by hydrophilic NHCs are also covered.

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Bysewski, Oliver, Andreas Winter, Phil Liebing e Ulrich S. Schubert. "Noble Metal Complexes of a Bis-Caffeine Containing NHC Ligand". Molecules 27, n. 13 (5 luglio 2022): 4316. http://dx.doi.org/10.3390/molecules27134316.

Testo completo

Abstract (sommario):

N-Heterocyclic carbenes (NHCs) have seen more and more use over the years. The go-to systems that are usually considered are derivatives of benzimidazole or imidazole. Caffeine possesses an imidazole unit and was already utilized as a carbene-type ligand; however, its use within a tridentate bis-NHC system has—to the best of our knowledge—not been reported so far. The synthesis of the ligand is straightforward and metal complexes are readily available via silver-salt metathesis. A platinum(II) and a palladium(II) complex were isolated and a crystal structure of the former was examined. For the Pt(II) complex, luminescence is observed in solid state as well as in solution.

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Jutand, Anny, Julien Pytkowicz, Sylvain Roland e Pierre Mangeney. "Mechanism of the oxidative addition of aryl halides to bis-carbene palladium(0) complexes". Pure and Applied Chemistry 82, n. 7 (4 maggio 2010): 1393–402. http://dx.doi.org/10.1351/pac-con-09-09-22.

Testo completo

Abstract (sommario):

Bis-N-heterocyclic carbenes Pd0 complexes, Pd0(NHC)2, are efficient catalysts in Heck reactions performed with aryl bromides or chlorides. The Pd0(NHC)2 that are not stable are generated in situ from PdII precursors PdY2(NHC)2 (Y = halides) after a chemical reduction. The latter procedure can be mimicked by an electrochemical reduction. The transient Pd0(NHCBn)2 is generated by electrochemical reduction of PdY2(NHCBn)2, and its reactivity in oxidative addition to aryl bromides and chlorides is characterized by the same electrochemical technique with the determination of the rate constants. Pd0(NHCBn)2 is found to be more reactive than the mixed complex Pd0(NHCBn)(PPh3). Both are the reactive species in an associative mechanism. Comparison with the isolated Pd0(NHCtBu)2 reveals that Pd0(NHCBn)2 is more reactive than Pd0(NHCtBu)2 even if the latter reacts via the mono-carbene Pd0(NHCtBu) in a dissociative mechanism. This suggests that the formation of mono-carbene Pd0(NHC) is not a guarantee for a fast oxidative addition because it is always generated at low concentration in its equilibrium with the related nonreactive bis-carbene Pd0(NHC)2.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Sureshbabu, Bemineni, Venkatachalam Ramkumar e Sethuraman Sankararaman. "Facile base-free in situ generation and palladation of mesoionic and normal N-heterocyclic carbenes at ambient conditions". Dalton Trans. 43, n. 28 (2014): 10710–12. http://dx.doi.org/10.1039/c4dt01112k.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Espinal-Viguri, Maialen, Victor Varela-Izquierdo, Fedor M. Miloserdov, Ian M. Riddlestone, Mary F. Mahon e Michael K. Whittlesey. "Heterobimetallic ruthenium–zinc complexes with bulky N-heterocyclic carbenes: syntheses, structures and reactivity". Dalton Transactions 48, n. 13 (2019): 4176–89. http://dx.doi.org/10.1039/c8dt05023f.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Azpíroz, Ramón, Mert Olgun Karataş, Vincenzo Passarelli, Ismail Özdemir, Jesús J. Pérez-Torrente e Ricardo Castarlenas. "Preparation of Mixed Bis-N-Heterocyclic Carbene Rhodium(I) Complexes". Molecules 27, n. 20 (18 ottobre 2022): 7002. http://dx.doi.org/10.3390/molecules27207002.

Testo completo

Abstract (sommario):

A series of mixed bis-NHC rhodium(I) complexes of type RhCl(η2-olefin)(NHC)(NHC’) have been synthesized by a stepwise reaction of [Rh(μ-Cl)(η2-olefin)2]2 with two different NHCs (NHC = N-heterocyclic carbene), in which the steric hindrance of both NHC ligands and the η2-olefin is critical. Similarly, new mixed coumarin-functionalized bis-NHC rhodium complexes have been prepared by a reaction of mono NHC complexes of type RhCl(NHC-coumarin)(η2,η2-cod) with the corresponding azolium salt in the presence of an external base. Both synthetic procedures proceed selectively and allow the preparation of mixed bis-NHC rhodium complexes in good yields.

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Ohki, Yasuhiro, e Hidetake Seino. "N-Heterocyclic carbenes as supporting ligands in transition metal complexes of N2". Dalton Transactions 45, n. 3 (2016): 874–80. http://dx.doi.org/10.1039/c5dt04298d.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Liang, Qiuming, Nina Jiabao Liu e Datong Song. "Constructing reactive Fe and Co complexes from isolated picolyl-functionalized N-heterocyclic carbenes". Dalton Transactions 47, n. 29 (2018): 9889–96. http://dx.doi.org/10.1039/c8dt02621a.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Shanmuganathan, Saravanakumar, Olaf Kühl, Peter Jones e Joachim Heinicke. "Nickel and palladium complexes of enolatefunctionalised N-heterocyclic carbenes". Open Chemistry 8, n. 5 (1 ottobre 2010): 992–98. http://dx.doi.org/10.2478/s11532-010-0071-6.

Testo completo

Abstract (sommario):

AbstractThe reaction of chloroethyltrimethylsilylether with 1-methylimidazole furnishes an ionic liquid that undergoes methanolysis to crystalline 2-hydroxyethylimidazolium chloride (crystal structure presented). Conversion to defined hydroxyethylimidazol-2-ylidene nickel complexes failed, but was accomplished with 1-methyl-3-acetophenyl-imidazolium bromide. The bis(NHC⋂O−) nickel(II) chelate is formed, rather than a methallylnickel monochelate, but with nickelocene a monochelate NiCp complex was detected. The bulky 1-(2,6-diisopropylphenyl)-3-(2’-phenyl-enolato)-imidazol-2-ylidene allylpalladium chloride was obtained in pure form. Attempts to generate catalysts for ethylene oligomerization by in situ techniques have failed so far whereas P⋂O− ligands, comparable by the P-C diagonal relationship, provide active catalysts.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Cingolani, Andrea, Cristiana Cesari, Stefano Zacchini, Valerio Zanotti, Maria Cristina Cassani e Rita Mazzoni. "Straightforward synthesis of iron cyclopentadienone N-heterocyclic carbene complexes". Dalton Transactions 44, n. 44 (2015): 19063–67. http://dx.doi.org/10.1039/c5dt03071d.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Dubey, Gurudutt, Nutan Mahawar, Tejender Singh, Nirjhar Saha, Subash C. Sahoo e Prasad V. Bharatam. "Thiazetidin-2-ylidenes as four membered N-heterocyclic carbenes: theoretical studies and the generation of complexes with N⁺ center". Physical Chemistry Chemical Physics 24, n. 2 (2022): 629–33. http://dx.doi.org/10.1039/d1cp04732a.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Gu, Shaojin, Jiehao Du, Jingjing Huang, Yun Guo, Ling Yang, Weilin Xu e Wanzhi Chen. "Unsymmetrical NCN-pincer mononuclear and dinuclear nickel(ii) complexes of N-heterocyclic carbene (NHC): synthesis, structure and catalysis for Suzuki–Miyaura cross-coupling". Dalton Transactions 46, n. 2 (2017): 586–94. http://dx.doi.org/10.1039/c6dt03944h.

Testo completo

Abstract (sommario):

Both two rare [(NHC)₂Ni₂-OH] type complexes and pincer-type [(NC_NHCN)Ni-Cl] complexes were synthesized using the same synthetic methodology by slight modulation of the N-substituents on the N-heterocyclic carbene ring.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Czerwiński, Paweł, e Michał Michalak. "Synthetic Approaches to Chiral Non-C 2-symmetric N-Heterocyclic Carbene Precursors". Synthesis 51, n. 08 (11 marzo 2019): 1689–714. http://dx.doi.org/10.1055/s-0037-1611733.

Testo completo

Abstract (sommario):

N-Heterocyclic carbenes and their metal complexes have found applications in many organic transformations. Apart from the privileged C 2-symmetry present in modern enantioselective catalysis, ligands bearing C 1-symmetry have witnessed growing attention due to the better control of process stereoselectivity in many cases. The present review summarizes, for the first time, the seminal synthetic efforts for the preparation of N-heterocyclic carbene precursors exhibiting C 1-symmetry. The well-established methods will be discussed in the light of recent achievements, giving a direct opportunity for comparison of the existing methods, and simultaneously a chance to find the best synthetic pathway for the ideal chiral ligand.1 Introduction2 Five-Membered Rings2.1 Five-Membered Saturated (Imidazolinium) Ring2.1.1 Amino Alcohol Derivatives2.1.2 Amino Acid Derivatives2.1.3 Amine and Diamine Derivatives2.2 Five-Membered Unsaturated Ring2.2.1 Cyclization Strategy2.2.2 Functionalization of the Existing N-Imidazole Ring3 Triazolium Salts3.1 Substitution in Oxadiazolium Salts3.2 Lactam-Derived Triazolium NHC (The Leeper and Knight Methodology)3.3 Monoterpenoid-Derived NHC Triazolium Salts3.4 Modifications of the Existing Triazole Ring4 Thiazole-Derived Salts4.1 Cyclization of a Thiazolium Ring4.2 Modifications of the Existing Thiazole Ring5 Summary and Outlook

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Haslinger, S., A. C. Lindhorst, J. W. Kück, M. Cokoja, A. Pöthig e F. E. Kühn. "Isocyanide substitution reactions at the trans labile sites of an iron(ii) N-heterocyclic carbene complex". RSC Advances 5, n. 104 (2015): 85486–93. http://dx.doi.org/10.1039/c5ra18270k.

Testo completo

Abstract (sommario):

A variety of isocyanide-substituted Fe(ii) N-heterocyclic carbene (NHC) complexes has been synthesized, starting from an Fe(ii) NHC complex with an equatorial, tetradentate bis(pyridyl-NHC) ligand (NCCN).

Gli stili APA, Harvard, Vancouver, ISO e altri

39

A Patil, Siddappa, Amy P Hoagland, Shivaputra A Patil e Alejandro Bugarin. "N-heterocyclic carbene-metal complexes as bio-organometallic antimicrobial and anticancer drugs, an update (2015–2020)". Future Medicinal Chemistry 12, n. 24 (dicembre 2020): 2239–75. http://dx.doi.org/10.4155/fmc-2020-0175.

Testo completo

Abstract (sommario):

N-heterocyclic carbenes (NHCs) are organic compounds that typically mimic the chemical properties of phosphines. NHCs have made a significant impact on the field of coordination and organometallic chemistry because they are easy to prepare and handle and because of their versatility and stability. Importantly, the physicochemical properties of NHCs can be easily fine-tuned by simple variation of substituents on the nitrogen atoms. Over the past few years, various NHC–metal complexes have been extensively used as metal-based drug candidates and catalysts (homogeneous or heterogeneous) for various applications. To help assist future work with these compounds, this review provides a thorough review on the latest information involving some biomedical applications of NHC–metal complexes. Specifically, this article focuses on recent advances in the design, synthesis, characterization and biomedical applications (e.g., antimicrobial and anticancer activity) of various NHC–metal complexes (metal: silver, gold, palladium, rhodium, ruthenium, iridium and platinum) covering work published from 2015 to 2020. It is hoped that the promising discoveries to date will help accelerate studies on the encouraging potential of NHC–metal complexes as a class of effective therapeutic agents.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Valdés, Hugo, Daniel Canseco-González, Juan Manuel Germán-Acacio e David Morales-Morales. "Xanthine based N-heterocyclic carbene (NHC) complexes". Journal of Organometallic Chemistry 867 (luglio 2018): 51–54. http://dx.doi.org/10.1016/j.jorganchem.2018.01.008.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Roy, Matthew M. D., Michael J. Ferguson, Robert McDonald e Eric Rivard. "Approaching monocoordination at a silver(i) cation". Chemical Communications 54, n. 5 (2018): 483–86. http://dx.doi.org/10.1039/c7cc08418h.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Wang, Yu-Ting, Bin-Bin Gao, Fan Wang, Shi-Yuan Liu, Hong Yu, Wen-Hua Zhang e Jian-Ping Lang. "Palladium(ii) and palladium(ii)–silver(i) complexes with N-heterocyclic carbene and zwitterionic thiolate mixed ligands: synthesis, structural characterization and catalytic properties". Dalton Transactions 46, n. 6 (2017): 1832–39. http://dx.doi.org/10.1039/c6dt04599e.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Visbal, Renso, e M. Concepción Gimeno. "N-heterocyclic carbene metal complexes: photoluminescence and applications". Chem. Soc. Rev. 43, n. 10 (2014): 3551–74. http://dx.doi.org/10.1039/c3cs60466g.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

44

DeJesus, Joseph F., Ryan W. F. Kerr, Deborah A. Penchoff, Xian B. Carroll, Charles C. Peterson, Polly L. Arnold e David M. Jenkins. "Actinide tetra-N-heterocyclic carbene ‘sandwiches’". Chemical Science 12, n. 22 (2021): 7882–87. http://dx.doi.org/10.1039/d1sc01007g.

Testo completo

Abstract (sommario):

Highly-symmetrical, thorium and uranium octakis-carbene ‘sandwich’ complexes have been prepared by ‘sandwiching’ the An(iv) cations between two anionic macrocyclic tetra-NHC ligands, one with sixteen atoms and the other with eighteen atoms.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Zhang, Dao, Yu He e Junkai Tang. "Chiral linker-bridged bis-N-heterocyclic carbenes: design, synthesis, palladium complexes, and catalytic properties". Dalton Transactions 45, n. 29 (2016): 11699–709. http://dx.doi.org/10.1039/c6dt00984k.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Cesari, C., S. Conti, S. Zacchini, V. Zanotti, M. C. Cassani e R. Mazzoni. "Sterically driven synthesis of ruthenium and ruthenium–silver N-heterocyclic carbene complexes". Dalton Trans. 43, n. 46 (2014): 17240–43. http://dx.doi.org/10.1039/c4dt02747g.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Turek, Jan, Illia Panov, Petr Švec, Zdeňka Růžičková e Aleš Růžička. "Non-covalent interactions in coinage metal complexes of 1,2,4-triazole-based N-heterocyclic carbenes". Dalton Trans. 43, n. 41 (2014): 15465–74. http://dx.doi.org/10.1039/c4dt01994f.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Al Nasr, Ibrahim, Nedra Touj, Waleed Koko, Tariq Khan, Ismail Özdemir, Sedat Yaşar e Naceur Hamdi. "Biological Activities of NHC–Pd(II) Complexes Based on Benzimidazolylidene N-heterocyclic Carbene (NHC) Ligands Bearing Aryl Substituents". Catalysts 10, n. 10 (15 ottobre 2020): 1190. http://dx.doi.org/10.3390/catal10101190.

Testo completo

Abstract (sommario):

N-heterocyclic carbene (NHC) precursors (2a–i), their pyridine-enhanced precatalyst preparation stabilization and initiation (PEPPSI)-themed palladium N-heterocyclic carbene complexes (3a–i) and palladium N-heterocyclic triphenylphosphines complexes (4a–i) were synthesized and characterized by elemental analysis and 1H NMR, 13C NMR, IR, and LC–MS spectroscopic techniques. The (NHC)Pd(II) complexes 3–4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites, and Vero cells in vitro. The biological assays indicated that all compounds are highly active against cancer cells, with an IC50 < 1.5 µg mL−1. Eight compounds proved antibacterial and antileishmanial activities, while only three compounds had strong antifungal activities against C. albicans. In our conclusion, compounds 3 (b, f, g, and h) and 4b are the most suitable drug candidates for anticancer, antimicrobial, and antiparasitical.

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Palacios, Laura, Andrea Di Giuseppe, Ricardo Castarlenas, Fernando J. Lahoz, Jesús J. Pérez-Torrente e Luis A. Oro. "Pyridine versus acetonitrile coordination in rhodium–N-heterocyclic carbene square-planar complexes". Dalton Transactions 44, n. 12 (2015): 5777–89. http://dx.doi.org/10.1039/c5dt00182j.

Testo completo

Abstract (sommario):

Experimental and theoretical studies on the factors that control the coordination chemistry of N-donor ligands in square-planar complexes of the type RhCl(NHC)L¹L² (NHC = N-heterocyclic carbene) are presented.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Lapshin, Ivan V., Anton V. Cherkasov, Andrey F. Asachenko e Alexander A. Trifonov. "Ln(ii) amido complexes coordinated by ring-expanded N-heterocyclic carbenes – promising catalysts for olefin hydrophosphination". Chemical Communications 56, n. 85 (2020): 12913–16. http://dx.doi.org/10.1039/d0cc05424k.

Testo completo

Abstract (sommario):

First Ln(ii) ring-expanded NHC complexes (er-NHC)Ln[N(SiMe₃)₂]₂ (Ln = Sm, Yb) are synthesized and proved to be highly efficient pre-catalysts for the intermolecular hydrophosphination of such indolent substrates as 1-alkenes, cyclohexene and norbornene.

Gli stili APA, Harvard, Vancouver, ISO e altri

Offriamo sconti su tutti i piani premium per gli autori le cui opere sono incluse in raccolte letterarie tematiche. Contattaci per ottenere un codice promozionale unico!