3769-82-2Relevant articles and documents
H2O2-mediated room temperature synthesis of 2-arylacetophenones from arylhydrazines and vinyl azides in water
Luo, Mengqiang,Zhang, Yaohong,Fang, Ping,Li, Yan,Qi, Chenze,Li, Yong,Shen, Runpu,Cheng, Kai,Wang, Hai
supporting information, p. 630 - 635 (2022/02/01)
An environmentally benign, cost-efficient and practical methodology for the room temperature synthesis of 2-arylacetophenones in water has been discovered. The facile and efficient transformation involves the oxidative radical addition of arylhydrazines with α-aryl vinyl azides in the presence of H2O2 (as a radical initiator) and PEG-800 (as a phase-transfer catalyst). From the viewpoint of green chemistry and organic synthesis, the present protocol is of great significance because of using cheap, non-toxic and readily available starting materials and reagents as well as amenability to gram-scale synthesis, which provides an attractive strategy to access 2-arylacetophenones.
Palladium-catalyzed synthesis of α-aryl acetophenones from styryl ethers and aryl diazonium saltsviaregioselective Heck arylation at room temperature
Venkatesh, Rapelly,Singh, Adesh Kumar,Lee, Yong Rok,Kandasamy, Jeyakumar
, p. 7832 - 7837 (2021/09/28)
Preparation of α-aryl acetophenones from styryl ethers and aryldiazonium salts is described. The reaction is catalyzed by palladium acetate at room temperature in the absence of ligand and base. The developed method is highly attractive in terms of reaction conditions, substrate scope, functional group tolerance and yields. Synthetic applications of the present method are demonstrated by preparing α-aryl indoles and 3-aryl isocoumarin from styryl ethers.
Azobenzene-Semicarbazone Enables Optical Control of Insect Sodium Channels and Behavior
Chen, Ruijia,Fu, Wen,Li, Zhong,Qiao, Zhi,Shao, Xusheng,Xu, Zhiping,Zhang, Yongchao
, p. 15554 - 15561 (2021/12/27)
Photopharmacology uses molecular photoswitches to establish control over the action of bioactive molecules. The application of photopharmacology in the research of invertebrate sodium channels has not been investigated. Here we report several photochromic ligands of metaflumizone. One ligand, termed ABM04, underwent reversible trans-cis isomerization under ultraviolet or blue light irradiation. cis-ABM04 had excellent larvicidal activity against mosquito larvae with an LC50 value of 4.39 μM and showed insecticidal activity against Mythimna separata with an LC50 value of 7.19 μM. However, trans-ABM04 was not found to have biological activity. ABM04 (10 μM) can induce depolarization of dorsal unpaired median neurons and enable the real-time photoregulation of mosquito larval behavior. The precise regulation of invertebrate sodium channels is realized for the first time, which provides a new strategy for the basic and accurate research of invertebrate sodium channels.
Heterogeneous visible-light-induced Meerwein hydration reaction of alkenes in water using mpg-C3N4 as a recyclable photocatalyst
Wang, Jingjing,Xue, Linshuang,Hong, Mei,Ni, Bangqing,Niu, Tengfei
, p. 411 - 416 (2020/02/13)
A green and efficient visible light induced Meerwein hydration reaction of alkenes in aqueous medium using mpg-C3N4 as a recyclabe photocatalyst has been disclosed. This protocol provides a direct approach for the preparation of racemic alcohols via a free radical mechanism. Water acted as both a solvent and a reagent without any additives or co-solvents. The metal-free heterogeneous semiconductor is found to be fully recyclable at least 5 times without any significant reduction in activity. The Meerwein hydration reaction has an excellent substrate scope and gave the desired products in moderate to high yields. Furthermore, this reaction could be carried out under solar light irradiation and is applicable for large-scale reactions with satisfactory results.
Porphyrins as Photoredox Catalysts in Csp2-H Arylations: Batch and Continuous Flow Approaches
De Souza, Aline A. N.,Silva, Nathalia S.,Müller, Andressa V.,Polo, André S.,Brocksom, Timothy J.,De Oliveira, Kleber T.
, p. 15077 - 15086 (2019/01/03)
We have investigated both batch and continuous flow photoarylations of enol-acetates to yield different α-arylated aldehyde and ketone building blocks by using diazonium salts as the aryl-radical source. Different porphyrins were used as SET photocatalysts, and photophysical as well as electrochemical studies were performed to rationalize the photoredox properties and suggest mechanistic insights. Notably, the most electron-deficient porphyrin (meso-tetra(pentafluorophenyl)porphyrin) shows the best photoactivity as an electron donor in the triplet excited state, which was rationalized by the redox potentials of excited states and the turnover of the porphyrins in the photocatalytic cycle. A two-step continuous protocol and multigram-scale reactions are also presented revealing a robust, cost-competitive, and easy methodology, highlighting the significant potential of porphyrins as SET photocatalysts.
Salicylic Acid-Catalyzed Arylation of Enol Acetates with Anilines
Felipe-Blanco, Diego,Gonzalez-Gomez, Jose C.
, p. 2773 - 2778 (2018/07/29)
α-Aryl ketones are both structure moieties commonly found in bioactive compounds and versatile synthetic intermediates for the preparation of drug-like molecules. An operationally simple and scalable protocol has been developed to prepare α-aryl ketones from readily available aromatic amines and enol acetates (or silyl enol ethers). This metal-free methodology features the use of salicylic acid as a convenient catalyst to promote the formation of aryl radicals from in-situ generated aryl diazonium salts, without demanding thermal or photochemical activation. The mild reaction conditions used are compatible with anilines substituted with diverse functionalities. Structural elaboration of some prepared α-aryl ketones was accomplished to illustrate their usefulness as building blocks. (Figure presented.).
Merging visible-light photoredox and micellar catalysis: Arylation reactions with anilines nitrosated in situ
Bu, Mei-Jie,Lu, Guo-Ping,Jiang, Jianzhong,Cai, Chun
, p. 3728 - 3732 (2018/08/12)
An aqueous photocatalytic system was designed by merging visible-light photoredox catalysis with micellar catalysis. Eosin B, an organic dye, was utilized as the photocatalyst, and Triton X-100 was employed as the surfactant; both are inexpensive and commercially available. This clean and energy-saving catalytic system enables photocatalytic reactions of the diazonium ion generated in situ to proceed smoothly in water without any co-solvents or additives at room temperature.
Expanding the Hammett Correlations for the Vinylheptafulvene Ring-Closure Reaction
Kilde, Martin Dr?hse,Hansen, Mia Harring,Broman, S?ren Lindb?k,Mikkelsen, Kurt V.,Nielsen, Mogens Br?ndsted
, p. 1052 - 1062 (2017/02/23)
A selection of 2,3-diarylated photochromic dihydroazulenes (DHAs) was prepared by following two different protocols. The first protocol relies on the synthesis of a 3-bromo-substituted dihydroazulene, which is subjected to a Suzuki cross-coupling reaction
Method for synthesizing aminoquinoxaline mixture
-
, (2017/09/26)
The invention discloses a method for synthesizing a mixture of 2-(4-aminophenyl)-3-phenyl-6-aminoquinoxaline and 3-(4-aminophenyl)-2-phenyl-6-aminoquinoxaline. The method comprises the following steps: by taking 4-nitrophenylacetic acid as an initial mate
Novel bisamide palladium(II) pincer complexes: effective catalysts in α-arylation of ketones
Kai, Wang,Liu, Dabin,Qian, Hua,Ye, Zhiwen
, p. 443 - 450 (2017/07/12)
Three benzenedicarboxamide ligands (L) were designed and synthesized, and each was used to prepare a palladium(II) complex Pd(L)Br and Pd(L)(OAc). These NCN pincer complexes were used to catalyze the α-arylations of a variety of ketones with aryl chlorides or bromides in various solvents, and moderate-to-excellent yields were obtained (up to 95%). Further research showed that unactivated and sterically hindered aryl halides and ketones are also suitable substrates for the synthesis of α-arylation. Graphical Abstract: [Figure not available: see fulltext.].
