27063-84-9Relevant academic research and scientific papers
Carbon Atom Insertion into Pyrroles and Indoles Promoted by Chlorodiazirines
Dherange, Balu D.,Kelly, Patrick Q.,Levin, Mark D.,Liles, Jordan P.,Sigman, Matthew S.
, p. 11337 - 11344 (2021/08/16)
Herein, we report a reaction that selectively generates 3-arylpyridine and quinoline motifs by inserting aryl carbynyl cation equivalents into pyrrole and indole cores, respectively. By employing α-chlorodiazirines as thermal precursors to the corresponding chlorocarbenes, the traditional haloform-based protocol central to the parent Ciamician-Dennstedt rearrangement can be modified to directly afford 3-(hetero)arylpyridines and quinolines. Chlorodiazirines are conveniently prepared in a single step by oxidation of commercially available amidinium salts. Selectivity as a function of pyrrole substitution pattern was examined, and a predictive model based on steric effects is put forward, with DFT calculations supporting a selectivity-determining cyclopropanation step. Computations surprisingly indicate that the stereochemistry of cyclopropanation is of little consequence to the subsequent electrocyclic ring opening that forges the pyridine core, due to a compensatory homoaromatic stabilization that counterbalances orbital-controlled torquoselectivity effects. The utility of this skeletal transform is further demonstrated through the preparation of quinolinophanes and the skeletal editing of pharmaceutically relevant pyrroles.
AIR-STABLE NI(0)-OLEFIN COMPLEXES AND THEIR USE AS CATALYSTS OR PRECATALYSTS
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Page/Page column 18, (2021/02/05)
The present invention relates to air stable, binary Ni(0)-olefin complexes and their use in organic synthesis.
LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, ELECTRONIC DEVICE, AND LIGHTING DEVICE
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Paragraph 0391-0392, (2017/10/26)
A novel organometallic complex with high reliability is provided. A light-emitting element includes an EL layer between a pair of electrodes. The EL layer includes at least a light-emitting layer. The light-emitting layer contains an organometallic complex. The organometallic complex includes a first ligand and a second ligand which are coordinated to a central metal. The HOMO is distributed over the first ligand, and the LUMO is distributed over the second ligand. The first ligand and the second ligand are cyclometalated ligands.
ORGANOMETALLIC COMPLEX, LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, ELECTRONIC DEVICE, AND LIGHTING DEVICE
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Paragraph 0333; 0334; 0335, (2017/10/31)
To provide a novel organometallic complex. The organometallic complex is represented by Formula (G1) and includes a central metal, a first ligand, and a second ligand. The first ligand and the second ligand are cyclometalated ligands. At least one of the
A modular, air-stable nickel precatalyst
Shields, Jason D.,Gray, Erin E.,Doyle, Abigail G.
supporting information, p. 2166 - 2169 (2015/05/13)
The synthesis and catalytic activity of [(TMEDA)Ni(o-tolyl)Cl], an air-stable, crystalline solid, is described. This complex is an effective precatalyst in a variety of nickel-catalyzed transformations. The lability of TMEDA allows a wide variety of ligands to be used, including mono- and bidentate phosphines, diimines, and N-heterocyclic carbenes. Preliminary mechanistic studies are also reported, which suggest that [(TMEDA)Ni(o-tolyl)Cl] can activate by either a Ni-B or Ni-Ni transmetalation event, depending on the reaction conditions.
Nickel-catalyzed dehydrogenative [4 + 2] cycloaddition of 1,3-dienes with nitriles
Ohashi, Masato,Takeda, Ippei,Ikawa, Masashi,Ogoshi, Sensuke
supporting information; experimental part, p. 18018 - 18021 (2011/12/13)
Pyridines, which comprise one of the most important classes of the six-membered heterocyclic compounds, are widely distributed in nature, and the transition-metal-catalyzed [2 + 2 + 2] cycloaddition reaction of two alkynes and a nitrile is one of the most powerful methods for preparing versatile, highly substituted pyridine derivatives. However, the lack of chemo- and regioselectivity is still a crucial issue associated with fully intermolecular [2 + 2 + 2] cycloaddition. The present study developed the Ni(0)-catalyzed intermolecular dehydrogenative [4 + 2] cycloaddition reaction of 1,3-butadienes with nitriles to give a variety of pyridines regioselectively.
Facile synthesis of cyclometalated ruthenium complexes with substituted phenylpyridines
Sasaki, Isabelle,Vendier, Laure,Sournia-Saquet, Alix,Lacroix, Pascal G.
, p. 3294 - 3302 (2007/10/03)
We have developed a new strategy that uses the Kroehnke synthesis for the preparation of various substituted phenylpyridines in excellent yields (up to 88%). Starting with the appropriate commercially available acetophenone, a variety of phenylpyridines substituted by either electron-donating (i.e. methyl, methoxy) or -withdrawing groups (i.e. bromide, nitro) on the phenyl ring are obtained in a two-step synthesis. The corresponding functionalized cyclometalated ruthenium complexes can be prepared with unusually high yields by using methanol as reaction solvent. The electrochemical data of the complexes demonstrate the strong σ-donating character of the anionic phenylpyridine ligand. X-ray analyses of four complexes show a shortening of the Ru-C bond associated with the elongation of only one of the five Ru-N bonds (trans effect). Wiley-VCH Verlag GmbH & Co, KGaA, 2006.
Formation and Rearrangement of Adducts from Benzyne and Substituted 2,1,3-Benzoselenadiazoles
Bryce, Martin R.,Reynolds, Colin D.,Hanson, Peter,Vernon, John M.
, p. 607 - 613 (2007/10/02)
A series of 5-(1,2-benzoselenazol-3-yl)pentadienonitrile derivatives (2) has been prepared by addition of benzyne to substituted 2,1,3-benzoselenadiazoles.Some of these adducts rearrange either thermally or photochemically to give 2-(2-pyridyl)phenyl selenocyanates (7), which are reduced to 2-phenylpyridine derivatives (6) or hydrolysed to give ultimately, diselenides (9).The crystal structure of one benzyne adduct (2b) is reported and the mechanism of its rearrangement discussed.
