80635-92-3Relevant academic research and scientific papers
Visible Light Induced Rhodium(I)-Catalyzed C?H Borylation
Thongpaen, Jompol,Manguin, Romane,Dorcet, Vincent,Vives, Thomas,Duhayon, Carine,Mauduit, Marc,Baslé, Olivier
supporting information, p. 15244 - 15248 (2019/10/22)
An efficient visible light induced rhodium(I)-catalyzed regioselective borylation of aromatic C?H bonds is reported. The photocatalytic system is based on a single NHC?RhI complex capable of both harvesting visible light and enabling the bond breaking/forming at room temperature. The chelating nature of the NHC-carboxylate ligand was critical to ensure the stability of the RhI complex and to provide excellent photocatalytic activities. Experimental mechanistic studies evidenced a photooxidative ortho C?H bond addition upon irradiation with blue LEDs, leading to a cyclometalated RhIII-hydride intermediate.
Pyridine sulfinates as general nucleophilic coupling partners in palladium-catalyzed cross-coupling reactions with aryl halides
Markovic, Tim,Rocke, Benjamin N.,Blakemore, David C.,Mascitti, Vincent,Willis, Michael C.
, p. 4437 - 4442 (2017/07/11)
Pyridine rings are ubiquitous in drug molecules; however, the pre-eminent reaction used to form carbon-carbon bonds in the pharmaceutical industry, the Suzuki-Miyaura cross-coupling reaction, often fails when applied to these structures. This phenomenon is most pronounced in 2-substituted pyridines, and results from the difficulty in preparing, the poor stability of, and low efficiency in reactions of pyridine-2-boronates. We demonstrate that by replacing these boronates with pyridine-2-sulfinates, a cross-coupling process of unrivalled scope and utility is realized. The corresponding 3-And 4-substituted pyridine variants are also efficient coupling partners. In addition, we apply these sulfinates in a library format to the preparation of medicinally relevant derivatives of the drugs varenicline (Chantix) and mepyramine (Anthisan).
Nitroarenes as the Nitrogen Source in Intermolecular Palladium-Catalyzed Aryl C–H Bond Aminocarbonylation Reactions
Zhou, Fei,Wang, Duo-Sheng,Guan, Xinyu,Driver, Tom G.
supporting information, p. 4530 - 4534 (2017/04/11)
A three-component palladium-catalyzed aminocarbonylation of aryl and heteroaryl sp2 C?H bonds using nitroarenes as the nitrogen source was achieved using Mo(CO)6 as the reductant and origin of the CO. This intermolecular C?H bond functionalization does not requires any exogenous ligand to be added, and our mechanism experiments indicate that the palladacycle catalyst serves two roles in the aminocarbonylation reaction: reduce the nitroarene to a nitrosoarene and activate the sp2 C?H bond.
P,N,N-Pincer nickel-catalyzed cross-coupling of aryl fluorides and chlorides
Wu, Dan,Wang, Zhong-Xia
, p. 6414 - 6424 (2014/08/18)
P,N,N-Pincer nickel complexes [Ni(Cl){N(2-R2PC6H 4)(2′-Me2NC6H4)}] (R = Ph, 3a; R = Pri, 3b; R = Cy, 3c) were synthesized and their catalysis toward the Kumada or Negishi cross-coupling reaction of aryl fluorides and chlorides was evaluated. Complex 3a effectively catalyzes the cross-coupling of (hetero)aryl fluorides with aryl Grignard reagents at room temperature. Complex 3a also catalyzes the cross-coupling of (hetero)aryl chlorides and arylzinc reagents at 80 °C with low catalyst loadings and good functional group compatibility. the Partner Organisations 2014.
Sulfonated N-heterocyclic carbenes for Pd-catalyzed sonogashira and suzuki-miyaura coupling in aqueous solvents
Roy, Sutapa,Plenio, Herbert
experimental part, p. 1014 - 1022 (2010/06/17)
The reactions of the N, N-diarylimidazolium and N, N-diarylimidazolinium salts with chlorosulfonic acid result in the formation of the respective disulfonated N-heterocyclic carbene (NHC) precursors in reasonable yields (46-77%). Water-soluble palladium catalyst complexes, in situ obtained from the respective sulfonated imidazolinium salt, sodium tetrachloropalladate (Na 2PdCl4) and potassium hydroxide (KOH) in water, were successfully applied in the copper-free Sonogashira coupling reaction in isopropyl alcohol/water mixtures using 0.2 mol% catalyst loading. The preformed (disulfonatedNHC)PdCl(cinnamyl) complex was used in aqueous Suzuki-Miyaura reactions at 0.1 mol% catalyst loading. The coupling protocol reported here is very useful for Sonogashira reactions of N- and 5-heterocyclic aryl bromides and chlorides with aryl- and alkylacetylenes.
Highly efficient suzuki-miyaura coupling of heterocyclic substrates through rational reaction design
Fleckenstein, Christoph A.,Plenio, Herbert
scheme or table, p. 4267 - 4279 (2009/05/07)
A dicyclohexyl(2-sulfo-9-(3-(4-sulfophenyl)propyl)-9H-fluoren-9-yl) phosphonium salt was synthesized in 64% overall yield in three steps from simple commercially available starting materials. The highly water-soluble catalyst obtained from the corresponding phosphine and [Na2PdCl4] enabled the Suzuki coupling of a broad variety of N- and S-heterocyclic substrates. Chloropyridines (-quinolines) and aryl chlorides were coupled with aryl-, pyridineor indoleboronic acids in quantitative yields in water/n-butanol solvent mixtures in the presence of 0.005-0.05 mol% of Pd catalyst at 100°C, chloropurines were quantitatively Suzuki coupled in the presence of 0.5 mol% of catalyst, and S-heterocyclic aryl chlorides and aryl- or 3-pyridylboronic acids required 0.01-0.05 mol % Pd catalyst for full conversion. The key to the high activity of the Pd-phosphine catalyst is the rational design of the reaction parameters (i.e., the presence of water in the reaction mixture, good solubility of reactants and catalyst in n-butanol/water (3:1), and the electron-rich and sterically demanding nature of the phosphine ligand).
Discovery of 4-{4-[3-(pyridin-2-yl)-1H-pyrazol-4-yl]pyridin-2-yl}-N- (tetrahydro-2H-pyran-4-yl)benzamide (GW788388): A potent, selective, and orally active transforming growth factor-β type I receptor inhibitor
Gellibert, Fran?oise,De Gouville, Anne-Charlotte,Woolven, James,Mathews, Neil,Nguyen, Van-Loc,Bertho-Ruault, Cécile,Patikis, Angela,Grygielko, Eugene T.,Laping, Nicholas J.,Huet, Stéphane
, p. 2210 - 2221 (2007/10/03)
Inhibitors of transforming growth factor β (TGF-β) type I receptor (ALK5) offer a novel approach for the treatment of fibrotic diseases such as renal, hepatic, and pulmonary fibrosis. The optimization of a novel phenylpyridine pyrazole series (1a) led to the identification of potent, selective, and orally active ALK5 inhibitors. The cellular potency and pharmacokinetics profiles of these derivatives were improved and several compounds presented antifibrotic activity when orally administered to rats in an acute liver model of dimethylnitrosamine- (DMN-) induced expression of collagen IA1 mRNA, a major gene contributing to excessive extra cellular matrix deposit. One of the most potent ALK5 inhibitors identified in this chemical series, compound 13d (GW788388), reduced the expression of collagen IA1 by 80% at a dose of 1 mg/kg twice a day (b.i.d.). This compound significantly reduced the expression of collagen IA1 mRNA when administered orally at 10 mg/kg once a day (u.i.d.) in a model of puromycin aminonucleoside-induced renal fibrosis.
Effect of substitution of methyl groups on the luminescence performance of IrIII complexes: Preparation, structures, electrochemistry, photophysical properties and their applications in organic light-emitting diodes (OLEDs)
Jung, Sungouk,Kang, Youngjin,Kim, Hyung-Sun,Kim, Yun-Hi,Lee, Chang-Lyoul,Kim, Jang-Joo,Lee, Sung-Koo,Kwon, Soon-Ki
, p. 3415 - 3423 (2007/10/03)
A series of dimethyl-substituted tris(pyridylphenyl)iridium(III) derivatives [(n-MePy-n′-MePh)3Ir] [n = 3, n′ = 4 (1); n = 4, n′ = 4 (2); n = 4, n′ = 5 (3); n = 5, n′ = 4 (4); n = 5, n′ = 5 (5)] have been synthesized and characterized to investigate the effect of the substitution of methyl groups on the solid-state structure and photo- and electroluminescence. The absorption, emission, cyclic voltammetry and electroluminescent performance of 1-5 have also been systematically evaluated. The structures of 2 and 4 have been determined by a single-crystal X-ray diffraction analysis. Under reflux (> 200 °C) in glycerol solution, fac-type complexes with a distorted octahedral geometry are predominantly formed as the major components in all cases. Electrochemical studies showed much smaller oxidation potentials relative to Ir(ppy)3 (Hppy = 2-phenylpyridine). All complexes exhibit intense green photoluminescence (PL), which has been attributed to metal-to-ligand charge transfer (MLCT) triplet emission. The maximum emission wavelengths of thin films of 1, 3, 4 and 5 at room temperature are in the range 529-536 nm, while 2 displays a blue-shifted emission band (λmax = 512 nm) with a higher PL quantum efficiency (ΦPL = 0.52) than those of complexes 1 and 3-5; this is attributed to a decrease of the intermolecular interactions. Multilayered organic light-emitting diodes (OLEDs) were fabricated by using three (2, 3 and 4) of these IrIII derivatives as dopant materials. The electroluminescence (EL) spectra of the devices, which have the maximum peaks at 509-522 nm, with shoulder peaks near 552 nm, are consistent with the PL spectra in solution at 298 K. The devices show operating voltages at 1 mA/cm 2 of 4,9, 5.6, 5,1, and 4.6 V for Ir(ppy)3, 2, 3, and 4, respectively. In particular, the device with 2 shows a higher external quantum efficiency (ηext = 11% at 1 mA/cm2) and brightness (4543 cd/m2 at 20 mA/cm2) than Ir(ppy)3 (ηext = 6.0% at 1 mA/cm2; 3156 cd/m2 at 20 mA/cm2) and other Ir(dmppy)3 derivatives, (dmppy = dimethyl-substituted ppy), under the same conditions. The methyl groups at the meta (Ph) and para (Py) positions to the Ir metal atom have a great influence on absorption, emission, redox potentials and electroluminescence. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
