613-33-2Relevant articles and documents
Nickel-catalysed direct C2-arylation of N-heterocyclic carbenes
Ho, Nga Kim T.,Neumann, Beate,Stammler, Hans-Georg,Menezes Da Silva, Vitor H.,Watanabe, Daniel G.,Braga, Ataualpa A. C.,Ghadwal, Rajendra S.
, p. 12027 - 12031 (2017)
A highly efficient nickel catalysed method for the direct C2-arylation of N-heterocyclic carbenes (NHCs) is reported. This protocol enables a facile access to C2-arylated imidazolium salts (NHC-Ar)X (X = Cl, Br, I or OTf). Experimental and theoretical studies suggest the viability of a Ni(i)/Ni(ii) catalytic pathway in which the dinuclear Ni(i) species [(NHC)NiX]2 plays a key role.
N-heterocyclic carbenes: III. N-heterocyclic carbene ligands based on abietane in Suzuki-Miyaura reaction
Glushkov,Valieva,Maiorova,Baigacheva,Gorbunov
, p. 230 - 235 (2011)
By reactions of N-alkyl- and N-arylimidazoles with methyl 12-bromoacetyldehydroabietate a series of unsymmetrically substituted chiral imidazolium bromides with the abietane fragment was synthesized. The salts obtained were suggested as new N-heterocyclic carbene ligands in the Suzuki-Miyaura reaction.
Single crystal to single crystal (SC-to-SC) transformation from a nonporous to porous metal-organic framework and its application potential in gas adsorption and Suzuki coupling reaction through postmodification
Sen, Rupam,Saha, Debraj,Koner, Subratanath,Brand?o, Paula,Lin, Zhi
, p. 5962 - 5971 (2015)
A new amino-functionalized strontium-carboxylate-based metal-organic framework (MOF) has been synthesized that undergoes single crystal to single crystal (SC-to-SC) transformation upon desolvation. Both structures have been characterized by single-crystal X-ray analysis. The desolvated structure shows an interesting 3D porous structure with pendent ￡NH2 groups inside the pore wall, whereas the solvated compound possesses a nonporous structure with DMF molecules on the metal centers. The amino group was postmodified through Schiff base condensation by pyridine-2-carboxaldehyde and palladium was anchored on that site. The modified framework has been utilized for the Suzuki cross-coupling reaction. The compound shows high activity towards the C￡C cross-coupling reaction with good yields and turnover frequencies. Gas adsorption studies showed that the desolvated compound had permanent porosity and was microporous in nature with a BET surface area of 2052 m2 g-1. The material also possesses good CO2 (8 wt %) and H2 (1.87 wt %) adsorption capabilities.
The study and application of three highly porous hyper-crosslinked catalysts possessing similar catalytic centers
Bi, Jiajun,Dong, Yahao,Meng, Di,Zhu, Dajian,Li, Tao
, p. 183 - 190 (2019)
Three new catalysts, in which salen ligands were successfully locked in knitting network polymers, were synthesized through the Friedel-Crafts reaction. As a result, the catalysts possessed high specific surface area as high as 512 m2/g with micro-/mesoporous structures, and showed layered morphologies. Owing to the high surface area, the abundant active centers and pores, the Poly-salen-a-Pd(II) displayed superior performance in the Suzuki-Miyaura coupling reaction of various substrates. In particular, the effect from similar catalytic centers for the catalytic properties and stability was investigated by a series of experiments and analyses such as thermogravimetric analysis (TGA), scanning and transmission electron microscopies (SEM and TEM), X-ray photoelectron spectroscopy (XPS), atomic absorption spectroscopy (AAS). Notably, three catalysts showed high activity in the reaction, and displayed excellent performance in the hot filtration experiments. This strategy is very cost-effective and convenient, which was highly suggestive to diverse professional audiences in a wide range of heterogeneous catalyst design and application.
Late stage Pd-catalyzed C-H bond functionalization: A powerful tool for the one step access to arylated Cyproheptadine and cyclobenzaprine derivatives
Atoui, Dhieb,Li, Haoran,Ben Salem, Ridha,Roisnel, Thierry,Caytan, Elsa,Soulé, Jean-Fran?ois,Doucet, Henri
, (2019)
The reactivity of Cyproheptadine and Cyclobenzaprine in Pd-catalyzed arylation via C-H bond functionalizations was investigated. From Cyproheptadine using aryl bromides as aryl sources and 5 mol% of a palladium catalyst, the C10-arylated Cyproheptadine derivatives were regioselectively obtained. The highest yields were obtained with electron-rich aryl bromides, but the reaction tolerated useful functional groups on the aryl bromide such as dimethylamino, methoxy, hydroxyl, alkyl, aryl, fluoro, chloro and trifluoromethyl. Cyclobenzaprine was also reactive under the same reaction conditions.
Synthesis of Symmetric and Nonsymmetric NiII Thiophosphinito PECSP (E = S, O) Pincer Complexes and Their Applications in Kumada Coupling under Mild Conditions
Hasche, Patrick,Joksch, Markus,Vlachopoulou, Georgia,Agarwala, Hemlata,Spannenberg, Anke,Beweries, Torsten
, p. 676 - 680 (2018)
The reaction of 1,3-dimercaptobenzene with iPr2PCl in the presence of the base NaH, furnishes the symmetric ligand [C6H4-1,3-(SPiPr2)2] (1a). The direct reaction of this ligand as well as of the literature-known nonsymmetric ligand [C6H4-1-(SPiPr2)-3-(OPiPr2)] (1b) with NiCl2 affords the symmetric bis(thiophosphinito) PSCSP pincer complex [{C6H3-2,6-(SPiPr2)2}NiCl] (2a) as well as the phosphinito–thiophosphinito POCSP pincer complex [{C6H3-2-(SPiPr2)-6-(OPiPr2)}NiCl] (2b). Both complexes were fully characterised and their catalytic performance in Kumada coupling of aryl halides and p-tolylmagnesium bromide under mild conditions was evaluated.
Catalytic activation of a single C-F bond in trifluoromethyl arenes
Dang, Hester,Whittaker, Aaron M.,Lalic, Gojko
, p. 505 - 509 (2016)
Synthetic methods for the direct transformation of ArCF3 to ArCF2R would enable efficient diversification of trifluoromethyl arenes and would be of great utility in medicinal chemistry. Unfortunately, the development of such methods has been hampered by the fundamental properties of C-F bonds, which are exceptionally strong and become stronger with increased fluorination of the carbon atom. Here, we describe a method for the catalytic reduction of ArCF3 to ArCF2H through a highly selective activation of a single C-F bond. Mechanistic studies reveal separate reaction pathways for the formation of ArCF2H and ArCH3 products and point to the formation of an unexpected intermediate as the source of the unusual selectivity for the mono-reduction.
A new aspect of nickel-catalyzed Grignard cross-coupling reactions: Selective synthesis, structure, and catalytic behavior of a T-shape three-coordinate nickel(I) chloride bearing a bulky NHC ligand
Miyazaki, Satoshi,Koga, Yuji,Matsumoto, Taisuke,Matsubara, Kouki
, p. 1932 - 1934 (2010)
Novel T-shape three-coordinate nickel(I) chlorides bearing an N-heterocyclic carbene ligand, NiCl(IPr)2 (IPr = 1,3-bis-(2,6- diisopropylphenyl)imidazolin-2-ylidene), were isolated by a reaction of Ni(0)(NHC)2 with aryl chlorides. This Ni(I) complex was shown to act as a catalyst in a cross-coupling reaction of aryl halides with phenylmagnesium chloride. The Royal Society of Chemistry 2010.
Iron(II) Corrole Anions
Caulfield, Kenneth P.,Conradie, Jeanet,Arman, Hadi D.,Ghosh, Abhik,Tonzetich, Zachary J.
, (2019)
Reduction of [Fe(TPC)(THF)] (TPC = trianion of 5,10,15-Triphenylcorrole) with KC8 generates the iron(II) corrole anion, K(THF)2[FeII(TPC)] (3a). Compound 3a represents the first example of an isolated and crystallographically characterized corrole complex of divalent iron. The compound adopts an intermediate-spin state (S = 1), displaying square-planar geometry about the iron atom. All-electron density functional theory (OLYP and B3LYP) calculations with STO-TZP basis sets indicate two essentially equienergetic d electron configurations, dxy2dz22dxz1dyz1 (occupation 1) and dxy2dz21dxz1dyz2 (occupation 2), as likely contenders for the ground state of [FeII(TPC)]-, with the optimized geometry of the former in slightly better agreement with the low-Temperature X-ray structure. Solutions of 3a react with carbon monoxide to afford the low-spin (S = 0) complex, [Fe(TPC)(CO)]-, whereas introduction of oxygen at-78 °C leads to a putative O2 adduct, [Fe(TPC)(O2)]-, which decays rapidly even at low temperatures. Treatment of 3a with organic electrophiles results in formal oxidative addition to give both iron(III) and iron(IV) corrole species. With iodomethane, [Fe(TPC)Me] is produced, illustrating the first instance of alkyl ligand coordination in an iron corrole complex.
Palladium-bisimidazol-2-ylidene complexes as catalysts for general and efficient Suzuki cross-coupling reactions of aryl chlorides with arylboronic acids
Zhang, Chunming,Trudell, Mark L.
, p. 595 - 598 (2000)
A series of bisimidazolium salts 1-6 were synthesized and evaluated as precursors to bisimidazol-2-ylidene ligands in palladium-catalyzed Suzuki cross-coupling reactions with aryl chlorides and arylboronic acids. The bisimidazolium salt 6 was found to be superior over imidazolium and other bisimidazolium salts affording high yields of biaryl products employing a wide variety of substrates. (C) 2000 Elsevier Science Ltd.
