3558-69-8Relevant academic research and scientific papers
A palladium catalyst system for the efficient cross-coupling reaction of aryl bromides and chlorides with phenylboronic acid: Synthesis and biological activity evaluation
Lamia, Boubakri,Chakchouk-Mtibaa, Ahlem,Hallouma, Bilel,Mansour, Lamjed,Mellouli, Lotfi,?zdemir, Ismail,Ya?ar, Sedat,Hamdi, Naceur
, (2017)
New benzimidazolium salts 1a-c and their palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c were designed, synthesized and structurally characterized by NMR (1H and 13C), IR, DART-TOF mass spectrometry and elemental analysis. Then these complexes 2-3 were employed in the Suzuki-Miyaura cross-coupling reaction of substituted arenes with phenylboronic acid under mild conditions in toluene and DMF/H2O (1/1) to afford functionalized biaryl derivatives in good to excellent yields. The antibacterial activity of palladium bis-N-heterocyclic carbene complexes 2a-c and palladium PEPPSI-type complexes 3a-c was measured by disc diffusion method against Gram positive and Gram negative bacteria. Compounds 2a, 2c and 3a-c exhibited potential antibacterial activity against four bacterial species among the five used indicator cells. The product 2b inhibits the growth of the all five tested microorganisms. Moreover, the antioxidant activity determination of these complexes 2-3, using 2.2-diphenyl-1-picrylhydrazyl (DPPH) as a reagent, showed that compounds 2a-c and 3b possess DPPH antiradical activity. The higher antioxidant activity was obtained from the product 2b which has radical scavenging activity comparable to that of the two used positive controls (gallic acid GA and tutylatedhydroxytoluene BHT ). Investigation of the anti-acetylcholinesterase activity of the studied complexes showed that compounds 2b, 3a, and 3b exhibited moderate activity at 100 μg/mL and product 2b is the most active.
Preparation and characterization of PEPPSI-palladium N-heterocyclic carbene complexes using benzimidazolium salts catalyzed Suzuki–Miyaura cross coupling reaction and their antitumor and antimicrobial activities
Boubakri, Lamia,Dridi, Khaireddine,Al-Ayed, Abdullah Sulaiman,?zdemir, ?smail,Yasar, Sedat,Hamdi, Naceur
, p. 516 - 527 (2019)
New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a–e, potassium carbonate (K2CO3) and palladium chloride (PdCl2) in pyridine (for 3a–e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K2CO3 in DMF-H2O was evaluated in Suzuki–Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g. for the Suzuki–Miyaura reaction: TON up to 370 and TOF up to 123.3 h?1). Both benzimidazolium salts 2a–e and complexes 3 have been characterized using spectroscopic data and elemental analysis. The antimicrobial activity of the N-heterocyclic carbene palladium complexes 3a–e varies with the nature of the ligands. Also, the IC50 values of both, complexes (3a–e) and benzimidazoles 2a–e, have been determined. In addition, the new palladium complexes were screened for their antitumor activity. Complexes 3e and 3d exhibited the highest antitumor effect with IC50 values 6.85 μg/mL against MCF-7 and 10.75 μg/mL against T47D, respectively.
Mechanism of Direct C-H Arylation of Pyridine via a Transient Activator Strategy: A Combined Computational and Experimental Study
Jia, Feiyun,Yin, Changzhen,Zeng, Yang,Sun, Rui,Ge, Yi-Cen,Xu, Dingguo,Li, Ruixiang,Chen, Hua,Zhang, Chunchun,Fu, Haiyan
, p. 10389 - 10397 (2018)
Recently, we realized the highly selective one-pot synthesis of 2,6-diarylpyridines by using a Pd-catalyzed direct C-H arylation approach via a transient activator strategy. Although methylation reagent as a transient activator and Cu(I) salt or oxide were found to be prerequisites, details regarding the mechanism remained unclear. In this paper, DFT calculations combined with experimental investigations were carried out to elucidate the principle features of this transformation. The results reveal (1) the origin of the exquisite diarylating selectivity of the pyridine under the transient strategy; (2) the possible demethylating reagent as the counteranion of the pyridinium salt; (3) the reason why Cu2O is a better Cu(I) resource than others.
Enaminones as building blocks in heterocyclic synthesis: A new one pot synthesis of polyfunctional substituted pyridines
Agamy, Samia Michel,Abdel-Khalik, Mervat Mohammed,Mohamed, Mona Hassan,Elnagdi, Mohammed Hilmy
, p. 1074 - 1078 (2001)
Enaminones react with a variety of active methyl and methylene reagents in presence of ammonium acetate to yield functionally substituted pyridines in good yields. The reaction proceeded via initial Michael addition across the double bond followed by cyclization. The reaction of enaminone with aromatic aldehyde in acetic acid/ammonium acetate afforded the dihydropyridine that was oxidized to the corresponding pyridine.
Pincerlike manganese complex and preparation method thereof, related ligand and preparation method thereof, catalyst composition and application
-
Paragraph 0159-0165, (2021/07/31)
The invention discloses a pincerlike manganese complex, a preparation method thereof, a ligand for preparation, a preparation method of the ligand, a catalyst composition taking the complex as an active component and application of the catalyst composition. According to the pincerlike manganese complex, a cycloalkyl ring is introduced into a ligand framework, and by regulating and controlling the cyclic tension, flexibility and steric hindrance of the cycloalkyl ring, the reactivity and stability of the manganese metal center can be effectively adjusted, and the catalytic activity and substrate applicability of a manganese metal system are remarkably improved. The catalyst composition taking the pincerlike manganese complex as an active component has the advantages of high catalyst activity, wide substrate application range, mild reaction conditions and the like in the process of preparing quinoline or pyridine derivatives by catalyzing dehydrogenation coupling reaction of o-amino aromatic alcohol or gamma-amino alcohol, ketone or secondary alcohol; and the synthesis advantages of low cost and stable performance are embodied, the operation is simple, and the yield is high.
Iron-Catalyzed Ring-Opening Reactions of Cyclopropanols with Alkenes and TBHP: Synthesis of 5-Oxo Peroxides
Lou, Chenhao,Wang, Xin,Lv, Leiyang,Li, Zhiping
, p. 7608 - 7612 (2021/10/02)
The ring opening of cyclopropanols is rarely used in multicomponent reactions. Herein we report the three-component reaction of cyclopropanols with alkenes and tert-butyl hydroperoxide (TBHP) catalyzed by an iron catalyst. This protocol enables the incorporation of both the β-carbonyl fragment and a peroxy unit across the C=C double bond regioselectively, thus allowing an efficient, facile access to 5-oxo peroxides. Modification of the biologically active molecules and various downstream derivatizations of the peroxides are also demonstrated.
Efficient access to quinolines and quinazolines by ruthenium complexes catalyzed acceptorless dehydrogenative coupling of 2-aminoarylmethanols with ketones and nitriles
Feng, Qi,Han, Zhangang,Hao, Zhiqiang,Huo, Shuaicong,Kong, Siqi,Lin, Jin,Lu, Guo-Liang,Zeng, Guang
, (2021/09/08)
Treatment of N,N,O-tridentate pyrazolyl-pyridinyl-alcohol ligands, 2-(CR1R2OH)-6-[3,5-(R3)2C3HN2]C5H3N (R1 = R2 = Me, R3 = H (L1H); R1 = Me, R2 = Ph, R3 = H (L2H); R1 = R2 = Ph, R3 = H (L3H); R1 = R2 = R3 = Me (L4H)) with RuCl3?xH2O in refluxing EtOH afforded the corresponding Ru(III) complexes L2RuCl (1a-1d), which were well characterized by IR, HR-MS and X-ray single crystal structural determination. These Ru complexes showed similarly high catalytic performance for both dehydrogenative couplings of 2-aminoarylmethanols with ketones and nitriles, giving the quinolines and quinazolines in good to excellent yields. This protocol provides an atom-economical and sustainable route to access various structurally important quinoline and quinazoline derivatives by using phosphine-free ligand based Ru catalysts.
Ruthenium complex and preparation method thereof and catalytic application
-
Paragraph 0104-0106; 0145-0146, (2021/01/24)
The invention discloses a ruthenium complex and a preparation method thereof and catalytic application. The ruthenium complex is reported for the first time. Research finds that the ruthenium complexhas the activity of catalytically synthesizing quinazoline and derivatives thereof or catalytically synthesizing quinoline and derivatives thereof. When the ruthenium complex provided by the inventionis used for catalytic synthesis of quinazoline and derivatives thereof or quinoline and derivatives thereof, the ruthenium complex has the advantages of mild reaction conditions, wide substrate range, high catalytic product yield and good functional group tolerance, and is significantly superior to the prior art.
Direct synthesis of ring-fused quinolines and pyridines catalyzed byNNHY-ligated manganese complexes (Y = NR2or SR)
Han, Mingyang,Lin, Qing,Liu, Qingbin,Liu, Song,Ma, Ning,Solan, Gregory A.,Sun, Wen-Hua,Wang, Zheng,Yan, Xiuli
, p. 8026 - 8036 (2021/12/27)
Four cationic manganese(i) complexes, [(fac-NNHN)Mn(CO)3]Br (Mn-1-Mn-3) and [(fac-NNHS)Mn(CO)3]Br (Mn-4) (whereNNHis a 5,6,7,8-tetrahydro-8-quinolinamine moiety), have been synthesized and evaluated as catalysts for the direct synthesis of quinolines and pyridines by the reaction of a γ-amino alcohol with a ketone or secondary alcohol;NNHS-ligatedMn-4proved the most effective of the four catalysts. The reactions proceeded well in the presence of catalyst loadings in the range 0.5-5.0 mol% and tolerated diverse functional groups such as alkyl, cycloalkyl, alkoxy, chloride and hetero-aryl. A mechanism involving acceptorless dehydrogenation coupling (ADC) has been proposed on the basis of DFT calculations and experimental evidence. Significantly, this manganese-based catalytic protocol provides a promising green and environmentally friendly route to a wide range of synthetically important substituted monocyclic, bicyclic as well as tricyclicN-heterocycles (including 50 quinoline and 26 pyridine examples) with isolated yields of up to 93%.
Cyclometalated pt complexes of cnc pincer ligands: Luminescence and cytotoxic evaluation
Garbe, Simon,Krause, Maren,Klimpel, Annika,Neundorf, Ines,Lippmann, Petra,Ott, Ingo,Brünink, Dana,Strassert, Cristian A.,Doltsinis, Nikos L.,Klein, Axel
supporting information, p. 746 - 756 (2020/03/30)
In the framework of our attempts to develop cyclometalated Pt(II) complexes toward bifunctional targeting inhibitors or agents for photodynamic therapy, diagnostics, and bioimaging, a series of bis-cyclometalated Pt(II) complexes [Pt(CNC)(L)] (L = DMSO, MeCN) containing various (CNC)2- ligands based on 2,6-diphenylpyridine were synthesized and characterized analytically and spectroscopically, focusing on their electrochemical, luminescence, and antiproliferative properties. Electrochemical experiments and UV-vis absorption spectroscopy suggest ligand-centered LUMOs and metal-centered HOMOs in line with DFT calculations. Extension of the ancillary phenyl to naphthyl cores and a central 4-phenylpyridine group instead of pyridine results in bathochromic shifts of the long-wavelength absorption bands ranging from 420 to 440 nm, with the latter shift being more pronounced. The complexes of the fused CNC heterocyclic systems dba (H2dba = dibenzo[c,h]acridine), db(ph)a (H2db(ph)a = 7-phenyldibenzo[c,h]acridine), and bzqph (HbzqphH = 2-phenylbenzo[h]quinoline) absorb far more red-shifted in the range 500-530 nm. All complexes show reversible first electrochemical reductions and irreversible oxidations with an electrochemical gap of about 3 V, roughly in line with the absorption energies. While the 2,6-diphenylpyridine complexes [Pt(CNC)(DMSO)] show no luminescence at ambient temperature in solution, the fused dba, db(ph)a, and bzqph derivatives are efficient triplet emitters at ambient temperature with emission wavelengths in the region 575-600 nm and quantum yields ranging from 7 to 23%. Vibrationally resolved emission spectra calculated in the framework of DFT faithfully reproduce the experimental data. TD-DFT calculations at the excited-state T1 geometry reveal intraligand π-π*/MLCT character of the emission for all three investigated complexes. Antiproliferative tests on selected complexes gave very different toxicities, ranging from lower than 1 μM to virtually nontoxic. The data allowed drawing some structure-activity relationships (SAR), even though variations in solubility could also significantly account for the different toxicities.
