42498-40-8Relevant academic research and scientific papers
Weak base-promoted selective rearrangement of oxaziridines to amidesviavisible-light photoredox catalysis
Park, Jin,Park, Sehoon,Jang, Gwang Seok,Kim, Ran Hui,Jung, Jaehoon,Woo, Sang Kook
, p. 9995 - 9998 (2021/10/06)
The selective rearrangement of oxaziridines to amidesviaa single electron transfer (SET) pathway is unexplored. In this study, we present a weak base-promoted selective rearrangement of oxaziridines to amidesviavisible-light photoredox catalysis. The developed method shows excellent functional group tolerance with a broad substrate scope and good to excellent yields. Furthermore, control experiments and density functional theory (DFT) calculations are performed to gain insight into the reactivity and selectivity.
Insight into Regioselective Control in Aerobic Oxidative C-H/C-H Coupling for C3-Arylation of Benzothiophenes: Toward Structurally Nontraditional OLED Materials
Bin, Zhengyang,Liao, Xingrong,Liu, Jiahui,Shen, Boming,Shi, Yang,Yan, Lipeng,Yang, Feng,Yang, Ge,Yang, Yudong,You, Jingsong,Yu, Peiyuan
supporting information, (2021/12/14)
The installation of (benzo)thiophene-containing biaryls via coupling reactions has become a staple in designing photoelectric materials. Undeniably, C-H/C-H cross-coupling reactions between two (hetero)aromatics would be a shortcut toward these structural fragments. While more reliable cross-coupling technologies are well-established to provide C2-arylated (benzo)thiophenes, efficient methods that arylate the C3-position remain underdeveloped. Herein we provide insight into the factors that determine regioselectivity switching for these cross-coupling reactions. X-ray crystallographic analysis gives solid evidence for the key roles of triflate in regioselective dearomatization and acetate in base-assisted anti-β-deprotonated rearomatization. The first isolation and X-ray characterization of a medium-sized dearomatized cyclometalated adduct involving both substrates provide extra insight into aerobic oxidative Ar-H/Ar-H cross-coupling reactions. The mechanistic breakthrough incubates the first example, enabling C-H/C-H-type C3-arylation of benzothiophenes. Finally, this chemistry is used to design blue-emitting thermally activated delayed fluorescence (TADF) materials with a helicene conformation that exhibit a high maximum external quantum efficiency of 25.4% in OLED.
CoFe2O4?SiO2-NH-βCD-BF3 as a supramolecular nanocomposite: Synthesis, characterization and catalytic activity
Hamadi, Hosein,Zanjani, Zohreh,Yadollahi, Mahtab
, (2019/11/14)
This manuscript describes synthesis of BF3-functionlized β-cylcodextrine grafted magnetic CoFe2O4 nanaoparticles as a hybrid magnetic nano-composite (CoFe2O4?SiO2-NH-βCD-BF3). The CoFe2O4?SiO2-NH-βCD-BF3 was fabricated by grafting of 6-O-toluenesulfonyl cyclodextrin (6-Ts-βCD) to 3-aminopropyl triethoxysilane coated magnetic CoFe2O4?SiO2 nanoparticles followed by combination with BF3. The CoFe2O4?SiO2-NH-βCD-BF3was characterized by FT-IR, TGA, VSM and SEM techniques. The feasibility of using CoFe2O4?SiO2-NH-βCD-BF3 as a magnetically recoverable catalyst was confirmed in the modified-Ritter reaction. The result showed that this novel nano-composite could serve as an efficient nanoreactor bearing super-acidic sites formed by immobilized BF3 and reuse at least for 6 times without loss in activity.
Nickel-catalyzed aminocarbonylation of Aryl/Alkenyl/Allyl (pseudo)halides with isocyanides and H2O
Li, Qiao,Cai, Yun,Jin, Hongwei,Liu, Yunkui,Zhou, Bingwei
supporting information, (2020/11/27)
Herein described is a nickel-catalyzed aminocarbonylation of aryl/alkenyl/allyl (pseudo)halides with isocyanides, providing aryl/alkenyl/allyl amides in 41% to 92% yields. Functional groups such as F, Cl, OMe, and heteroaromatic rings are compatible in the reaction. A Ni(0)/Ni(II) catalytic cycle is proposed based on preliminary experiments and previous literature. The reaction features readily available nickel salt, broad functional group tolerance, and simple reaction conditions.
Organophotoredox-Mediated Amide Synthesis by Coupling Alcohol and Amine through Aerobic Oxidation of Alcohol
Samanta, Samya,Shah, Sk. Sheriff,Shee, Maniklal,Singh, Amit Kumar,Singh, N. D. Pradeep,Venkatesh, Yarra
, (2020/03/05)
The combination of an organic photocatalyst [4CzIPN (1,2,3,5-tetrakis(carbazol-9-yl)-4,6 dicyanobenzene) or 5MeOCzBN (2,3,4,5,6-pentakis(3,6-dimethoxy-9 H-carbazol-9-yl)benzonitrile)], quinuclidine, and tetra-n-butylammonium phosphate (hydrogen-bonding catalyst) was employed for amide bond formations. The hydrogen-bonded OH group activated the adjacent C?H bond of alcohols towards hydrogen atom transfer (HAT) by a radical species. The quinuclidinium radical cation, generated through single-electron oxidation of quinuclidine by the photocatalyst, employed to abstract a hydrogen atom from the α-C?H bond of alcohols selectively due to a polarity effect-produced α-hydroxyalkyl radical, which subsequently converted to the corresponding aldehyde under aerobic conditions. Then the coupling of the aldehyde and an amine formed a hemiaminal intermediate that upon photocatalytic oxidation produced the amide.
Ionic liquid catalyzed Ritter reaction/Pd-catalyzed directed Ortho-arylation; facile access to diverse libraries of biaryl-amides from Aryl-nitriles
Sutar, Suraj M.,Savanur, Hemantkumar M.,Kalkhambkar, Rajesh G.,Borosky, Gabriela L.,Aridoss, Gopalakrishnan,Laali, Kenneth K.
supporting information, (2020/10/30)
Diverse libraries of biaryl-amides bearing N-t-butyl and N-adamantyl groups were synthesized in two steps by the Ritter reaction of aryl-nitriles, using tBuOH and AdaOH as carbocation precursors, and employing [BMIM(SO3H)][OTf] (neat or with [B
Oxidative C?H/C?H Cross-Coupling Reactions between N-Acylanilines and Benzamides Enabled by a Cp*-Free RhCl3/TFA Catalytic System
Shi, Yang,Zhang, Luoqiang,Lan, Jingbo,Zhang, Min,Zhou, Fulin,Wei, Wenlong,You, Jingsong
supporting information, p. 9108 - 9112 (2018/07/25)
By making use of a dual-chelation-assisted strategy, a completely regiocontrolled oxidative C?H/C?H cross-coupling reaction between an N-acylaniline and a benzamide has been accomplished for the first time. This process constitutes a step-economic and highly efficient pathway to 2-amino-2′-carboxybiaryl scaffolds from readily available substrates. A Cp*-free RhCl3/TFA catalytic system was developed to replace the [Cp*RhCl2]2/AgSbF6 system generally used in oxidative C?H/C?H cross-coupling reactions between two (hetero)arenes (Cp=pentamethylcyclopentadienyl, TFA=trifluoroacetic acid). The RhCl3/TFA system avoids the use of the expensive Cp* ligand and AgSbF6. As an illustrative example, the procedure developed herein greatly streamlines the total synthesis of the naturally occurring benzo[c]phenanthridine alkaloid oxynitidine, which was accomplished in excellent overall yield.
Cp?CoIII-Catalyzed syn-Selective C-H Hydroarylation of Alkynes Using Benzamides: An Approach Toward Highly Conjugated Organic Frameworks
Bera, Sourav Sekhar,Debbarma, Suvankar,Ghosh, Avick Kumar,Chand, Santanu,Maji, Modhu Sudan
, p. 420 - 430 (2017/04/26)
Hydroarylation of internal alkynes by cost-effective CoIII-catalysis, directed by N-tert-butyl amides, is achieved to avail mono- or dihydroarylated amide products selectively in an atom and step economic way. Several important functional groups were tolerated under the reaction conditions, and syn-hydroarylation products were exclusively isolated. Notably, a 4-fold C-H hydroarylation provided a highly conjugated organic framework in one step. Kinetic study with extensive deuterium labeling experiments were performed to support the proposed mechanism.
A Visible-Light-Driven, Metal-free Route to Aromatic Amides via Radical Arylation of Isonitriles
Malacarne, Marco,Protti, Stefano,Fagnoni, Maurizio
supporting information, p. 3826 - 3830 (2017/11/15)
The photochemical metal-free carboamidation of aryl radicals has been exploited for the preparation of aromatic amides, including hetero- and polyaromatic derivatives, under visible light irradiation of arylazo sulfones in the presence of isocyanides in aqueous acetonitrile. The process was useful for the smooth preparation of the antidepressant moclobemide. (Figure presented.).
Bu4NI-Catalyzed Oxygen-Centered Radical Addition between Acyl Peroxides and Isocyanides
Chen, Meng,Li, Yang,Tang, Hong,Ding, Hao,Wang, Kai,Yang, Lingen,Li, Cuiting,Gao, Meng,Lei, Aiwen
supporting information, p. 3147 - 3150 (2017/06/23)
A novel oxygen-centered radical addition between acyl peroxides and isocyanides has been developed. A diverse collection of valuable arylcarboxyamides were easily synthesized by this protocol. From the preliminary mechanistic study, the elimination of carbon dioxide affords the product via an intramolecular rearrangement.
