14002-52-9Relevant academic research and scientific papers
Palladium-catalyzed annulation of 2-substituted silylethynyloxybiaryls through δ-C-H activation
Minami, Yasunori,Anami, Tomohiro,Hiyama, Tamejiro
, p. 1791 - 1793 (2014)
The intramolecular hydroarylation of 2-(silylethynyloxy)-biphenyls takes place with the aid of a palladium catalyst to give 6-methylene-6H-d ibenzo[b,d]pyrans. The product can be transformed into 6,6-disubstituted dibenzopyrans via protodesilylation, foll
Novel benzimidazole derivatives as electron-transporting type host to achieve highly efficient sky-blue Phosphorescent organic light-emitting diode (PHOLED) device
Huang, Jau-Jiun,Leung, Man-Kit,Chiu, Tien-Lung,Chuang, Ya-Ting,Chou, Pi-Tai,Hung, Yu-Hsiang
, p. 5398 - 5401 (2014)
The development of benzimidazole substituted biphenyls as electron-transporting hosts for bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium-(III) is reported. Under the optimized conditions, the organic light-emitting diode (OLED) a
A scalable process for the synthesis of 2-methyl-1,4,5,6- tetrahydroimidazo[4,5-d][1]benzazepine monohydrate and 4-[(biphenyl-2- ylcarbonyl)amino]benzoic acid: Two new key intermediates for the synthesis of the AVP antagonist conivaptan hydrochloride
Tsunoda, Takashi,Yamazaki, Atsuki,Mase, Toshiyasu,Sakamoto, Shuichi
, p. 593 - 598 (2005)
A process for the multikilogram synthesis of the dual vasopressin-receptor antagonist, conivaptan hydrochloride, has been developed. This method relies on the introduction of operationally simple chemistry during the final stages of the process when two k
Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates
Chattopadhyay, Buddhadeb,Hassan, Mirja Md Mahamudul,Hoque, Md Emdadul
supporting information, p. 5022 - 5037 (2021/05/04)
Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.
Rh(iii)-Catalyzed three-component cascade annulation to produce theN-oxopropyl chain of isoquinolone derivatives
He, Yuan,Liao, Xian-Zhang,Dong, Lin,Chen, Fen-Er
supporting information, p. 561 - 567 (2021/02/06)
Developing powerful methods to introduce versatile functional groups at theN-substituents of isoquinolone scaffolds is still a great challenge. Herein, we report a novel three-component cascade annulation reaction to efficiently construct theN-oxopropyl chain of isoquinolone derivativesviarhodium(iii)-catalyzed C-H activation/cyclization/nucleophilic attack, with oxazoles used both as the directing group and potential functionalized reagents.
Aryne Multicomponent Reactions by Directed C?H Activation
Sunnam, Sunil Kumar,Belani, Jitendra D.
supporting information, p. 8846 - 8850 (2021/05/31)
Arylation via ortho C?H activation by the aid of directing groups has been explored recently by many researchers. Herein, a palladium-catalyzed C?H arylation using 8-aminoquinoline as a bidentate directing group has been developed. The reaction furnishes only C?H arylation, unlike previous methods where cyclization to corresponding isoquinolones is observed. More interestingly, sequential C?H functionalization was observed when methylacrylate and acrylonitrile was added; this led to C?H olefination with the aryl group, which was installed from the aryne precursor.
N-Ammonium Ylide Mediators for Electrochemical C-H Oxidation
Saito, Masato,Kawamata, Yu,Meanwell, Michael,Navratil, Rafael,Chiodi, Debora,Carlson, Ethan,Hu, Pengfei,Chen, Longrui,Udyavara, Sagar,Kingston, Cian,Tanwar, Mayank,Tyagi, Sameer,McKillican, Bruce P.,Gichinga, Moses G.,Schmidt, Michael A.,Eastgate, Martin D.,Lamberto, Massimiliano,He, Chi,Tang, Tianhua,Malapit, Christian A.,Sigman, Matthew S.,Minteer, Shelley D.,Neurock, Matthew,Baran, Phil S.
supporting information, p. 7859 - 7867 (2021/05/26)
The site-specific oxidation of strong C(sp3)-H bonds is of uncontested utility in organic synthesis. From simplifying access to metabolites and late-stage diversification of lead compounds to truncating retrosynthetic plans, there is a growing need for new reagents and methods for achieving such a transformation in both academic and industrial circles. One main drawback of current chemical reagents is the lack of diversity with regard to structure and reactivity that prevents a combinatorial approach for rapid screening to be employed. In that regard, directed evolution still holds the greatest promise for achieving complex C-H oxidations in a variety of complex settings. Herein we present a rationally designed platform that provides a step toward this challenge using N-ammonium ylides as electrochemically driven oxidants for site-specific, chemoselective C(sp3)-H oxidation. By taking a first-principles approach guided by computation, these new mediators were identified and rapidly expanded into a library using ubiquitous building blocks and trivial synthesis techniques. The ylide-based approach to C-H oxidation exhibits tunable selectivity that is often exclusive to this class of oxidants and can be applied to real-world problems in the agricultural and pharmaceutical sectors.
Ru(ii)-catalyzed allenylation and sequential annulation of: N -tosylbenzamides with propargyl alcohols
Kumar, Shreemoyee,Nair, Akshay M.,Volla, Chandra M. R.
, p. 6280 - 6283 (2021/07/02)
We hereby report Ru(ii)-catalyzed C(sp2)-H allenylation of N-tosylbenzamides to access multi-substituted allenylamides. Furthermore, the allenylamides were converted to the corresponding isoquinolone derivatives via base mediated annulation. The current protocol features low catalyst loading, mild reaction conditions, high functional group compatibility and desired scalability. The unique functionality of the afforded allenes allowed further transformations to expand the practicality of the protocol. This journal is
Ni-Catalyzed Aryl Sulfide Synthesis through an Aryl Exchange Reaction
Isshiki, Ryota,Kurosawa, Miki B.,Muto, Kei,Yamaguchi, Junichiro
supporting information, p. 10333 - 10340 (2021/07/21)
A Ni-catalyzed aryl sulfide synthesis through an aryl exchange reaction between aryl sulfides and a variety of aryl electrophiles was developed. By using 2-pyridyl sulfide as a sulfide donor, this reaction achieved the synthesis of aryl sulfides without using odorous and toxic thiols. The use of a Ni/dcypt catalyst capable of cleaving and forming aryl-S bonds was important for the aryl exchange reaction between 2-pyridyl sulfides and aryl electrophiles, which include aromatic esters, arenol derivatives, and aryl halides. Mechanistic studies revealed that Ni/dcypt can simultaneously undergo oxidative additions of aryl sulfides and aromatic esters, followed by ligand exchange between the generated aryl-Ni-SR and aryl-Ni-OAr species to furnish aryl exchanged compounds.
Mechanochemical-Cascaded C-N Cross-Coupling and Halogenation Using N-Bromo- And N-Chlorosuccinimide as Bifunctional Reagents
Bera, Shyamal Kanti,Mal, Prasenjit
, p. 14144 - 14159 (2021/09/13)
Exploration of alternative energy sources for chemical transformations has gained significant interest from chemists, and mechanochemistry is one of those sources. Herein, we report the use of N-bromosuccinimides (NBS) and N-chlorosuccinimides (NCS) as bifunctional reagents for a cascaded C-N bond formation and subsequent halogenation reactions. Under the solvent-free mechanochemical (ball-milling) conditions, the synthesis of a wide range of phenanthridinone derivatives from N-methoxy-[1,1′-biphenyl]-2-carboxamides is accomplished. During the reactions, NBS and NCS first assisted the oxidative C-N coupling reaction and subsequently promoted a halogenation reaction. Thus, the role of NBS and NCS was established to be bifunctional. Overall, a mild, solvent-free, convenient, one-pot, and direct synthesis of various bromo- and chloro-substituted phenanthridinone derivatives was achieved.
