92855-12-4Relevant academic research and scientific papers
Synthesis of Polyethylenes with Controlled Branching with α-Diimine Nickel Catalysts and Revisiting Formation of Long-Chain Branching
Pei, Lixia,Liu, Fengshou,Liao, Heng,Gao, Jie,Zhong, Liu,Gao, Haiyang,Wu, Qing
, p. 1104 - 1113 (2018)
The synthesis of polyethylenes with precise branching, especially long-chain branching (LCB), using ethylene monomer as a single feedstock is of a significant academic and industrial interest. On the basis of the ortho-aryl effect, a series of α-diimine n
Radical Borylative Cyclization of Isocyanoarenes with N-Heterocyclic Carbene Borane: Synthesis of Borylated Aza-arenes
Liu, Yao,Li, Ji-Lin,Liu, Xu-Ge,Wu, Jia-Qiang,Huang, Zhi-Shu,Li, Qingjiang,Wang, Honggen
supporting information, p. 1891 - 1897 (2021/03/08)
Borylated aza-arenes are of great importance in the area of organic synthesis. A radical borylative cyclization of isocyanoarenes with N-heterocyclic carbene borane (NHC-BH3) under metal-free conditions was developed. The reaction allows the efficient assembly of several types of borylated aza-arenes (phenanthridines, benzothiazoles, etc.), which are difficult to access using alternative methods. Mild reaction conditions, a good functional-group tolerance, and generally good efficiencies were observed. The utility of these products is demonstrated, and the mechanism is discussed.
α-Bromoacrylic Acids as C1 Insertion Units for Palladium-Catalyzed Decarboxylative Synthesis of Diverse Dibenzofulvenes
Zhang, Minghao,Deng, Wenbo,Sun, Mingjie,Zhou, Liwei,Deng, Guobo,Liang, Yun,Yang, Yuan
supporting information, p. 5744 - 5749 (2021/08/18)
Herein α-bromoacrylic acids have been employed as C1 insertion units to achieve the palladium-catalyzed [4 + 1] annulation of 2-iodobiphenyls, which provides an efficient platform for the construction of diverse dibenzofulvenes. This protocol enables the formation of double C(aryl)-C(vinyl) bonds via a C(vinyl)-Br bond cleavage and decarboxylation. It is particularly noteworthy that the method features a broad substrate scope, and various interesting frameworks, such as bridged ring, fused (hetero)aromatic ring, and divinylbenzene, can be successfully incorporated into the products.
Atmosphere-Controlled Palladium-Catalyzed Divergent Decarboxylative Cyclization of 2-Iodobiphenyls and α-Oxocarboxylic Acids
Zhou, Liwei,Sun, Mingjie,Zhou, Fengru,Deng, Guobo,Yang, Yuan,Liang, Yun
supporting information, p. 7150 - 7155 (2021/09/18)
A novel palladium-catalyzed divergent decarboxylative cyclization of 2-iodobiphenyls and α-oxocarboxylic acids utilizing the atmosphere as a controlled switch is reported. Under the protection of a nitrogen atmosphere, tribenzotropones are synthesized by a [4 + 3] decarboxylative cyclization. Employing a palladium/O2 system enables a [4 + 2] decarboxylative cyclization to assemble triphenylenes. Notably, preliminary mechanistic studies indicate that the formation of triphenylenes involves a double decarboxylation.
Palladium-Catalyzed C-H Amination/[2 + 3] or [2 + 4] Cyclization via C(sp3or sp2)-H Activation
An, Yang,Ding, Ya-Nan,Gou, Xue-Ya,Li, Qiao,Li, Yuke,Liang, Yong-Min,Zhang, Xiao-Yan,Zhang, Zhe
supporting information, p. 7961 - 7965 (2021/10/25)
This report describes a palladium-catalyzed Catellani reaction consisting of amination/[2 + 3] or [2 + 4] cyclization via a carboxylate ligand-exchange strategy. This method effectively activates ortho-substituents that avoid a second C-H palladation. The scope of substrates was broad, o-methyl-substituted iodoarenes were applied to the reaction smoothly, and o-phenyl-substituted iodoarenes can also be obtained by this method. In terms of mechanism, density functional theory calculations proved the sequence of the key five-membered aryl-norbornene-palladacycle intermediate formation and C(sp3 or sp2)-H activation.
Oxaspiro chiral phosphoric acid and preparation method and application thereof
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Paragraph 0074-0077, (2021/07/24)
The invention provides oxaspiro chiral phosphoric acid and a preparation method and application thereof. The oxaspiro chiral phosphoric acid with the structure shown in the formula (A) has the good catalytic activity and the good stereoselectivity, and experimental results show that the oxaspiro chiral phosphoric acid provided by the invention is used for asymmetric synthesis of chiral biaryl-2-amine compounds, the enantioselectivity of the obtained product is greater than 97%, and the oxaspiro chiral phosphoric acid has great potential and practical value and is high in product yield.
Synthesis of Fluorescent 4-Azapyrenes by Palladium(II)-Catalyzed Dual C?H Bond Activation and Annulation
Hsiao, Huan-Chang,Annamalai, Pratheepkumar,Jayakumar, Jayachandran,Sun, Shang-You,Chuang, Shih-Ching
supporting information, p. 1695 - 1701 (2021/02/12)
Unique dual-emissive and deep-blue/green fluorescent multi-substituted 4-azapyrenes with bathochromic shift emission, quantum yields up to 0.60 and long excited-state lifetime were synthesized successfully by annulative π-extension reactions. This synthesis constitutes a palladium-catalyzed dehydrogenative annulation of N-acyl-2-aminobiaryls with in situ 1,3-diynes as a key step, giving substituted phenanthrenes via a rollover C?H bond activation, followed by Bischler-Napieralski cyclization. Further π-extension by superacid-mediated cyclization produced a blue fluorescent naphtho 4-azapyrene. (Figure presented.).
Electrochemical Palladium-Catalyzed Intramolecular C—H Amination of 2-Amidobiaryls for Synthesis of Carbazoles
Gao, Xinlong,Lei, Aiwen,Wang, Pan,Wang, Qingqing,Zhang, Heng,Zhang, Xiaojing
supporting information, p. 143 - 148 (2020/12/18)
The synthesis of carbazoles based on the electrochemical Pd-catalyzed intramolecular C—H amination of 2-amidobiaryls through oxidative cross coupling has been achieved under mild reaction conditions. The reaction can be carried out in undivided cell without the addition of external chemical oxidant. Besides good functional group compatibility, the desired carbazoles can be scaled up and modified easily. Compared with previous methods, this protocol affords a simple and sustainable avenue for the construction of carbazoles.
Photocatalytic xanthate-based radical addition/cyclization reaction sequence toward 2-biphenyl isocyanides: Synthesis of 6-alkylated phenanthridines
López-Mendoza, Pedro,Miranda, Luis D.
supporting information, p. 3487 - 3491 (2020/05/25)
A photocatalytic xanthate-based radical addition/cyclization reaction cascade toward 2-biphenylisocyanides is described as a practical and modular approach to 6-alkylated phenanthridines. The use of xanthates as radical precursors allowed the synthesis of diversely 6-substituted phenanthridines. Electrophilic radicals derived from nitriles, aromatic and aliphatic ketones, malonates, and amide derivatives, as well as radicals derived from phthalimidomethyl and benzylic derivatives were successfully introduced. The reaction proceeds under mild conditions without a stoichiometric amount of oxidant. Thirty novel phenanthridine scaffolds were synthesized with yields ranging from 24 to 76%.
Ir(III) Cyclometalated Complexes Containing Phenylphenanthridine Ligands with Different Substitutions: Effects on the Electrochemiluminescence Properties
De Cola, Luisa,Fernandez-Hernandez, Jesus M.,Fr?hlich, Roland,Iordache, Adriana,Josel, Hans-Peter,Longhi, Elena
supporting information, (2020/06/08)
A family of neutral bis-cyclometalated Ir(III) complexes based on phenanthridine (phent) derivates as cyclometalating ligands and picolinate as an ancillary ligand are described. The influence of extended conjugation, rigidity, and hydrophobicity as well as the electronic nature of the substituents were investigated in relation to the photoluminescence, PL, and electrochemiluminescence, ECL, properties. A significant increase of ECL in aqueous media is observed upon extension of the aromatic system or by substituting the phenyl with a dibenzofurane moiety, in compounds 2 and 3, respectively. Under real immunoassay conditions, these complexes achieve up to 4-fold higher ECL efficiency than the commercial ruthenium standard. These values, among the highest reported in the literature under these conditions, confirm the potential of iridium complexes as alternative labels in commercial instruments.
