29776-35-0Relevant academic research and scientific papers
Ynonylation of Acyl Radicals by Electroinduced Homolysis of 4-Acyl-1,4-dihydropyridines
Luo, Xiaosheng,Wang, Ping
, p. 4960 - 4965 (2021/07/20)
Herein we report the conversion of 4-Acyl-1,4-dihydropyridines (DHPs) into ynones under electrochemical conditions. The reaction proceeds via the homolysis of acyl-DHP under electron activation. The resulting acyl radicals react with hypervalent iodine(III) reagents to form the target ynones or ynamides in acceptable yields. This mild reaction condition allows wider functionality tolerance that includes halides, carboxylates, or alkenes. The synthetic utility of this methodology is further demonstrated by the late-stage modification of complex molecules.
Atom-Economic Synthesis of Highly Functionalized Bridged Ring Systems Initiated by Ring Expansion of Indene-1,3-dione
Mu, Yuanyang,Yao, Qiyi,Yin, Liqiang,Fu, Siyi,Wang, Mengdan,Yuan, Yang,Kong, Lingkai,Li, Yanzhong
, p. 6755 - 6764 (2021/05/06)
An atom economic procedure for the regioselective synthesis of bridged seven-membered-ring compounds from simple reactants such as ynones and indene-1,3-dione has been developed. This process was realized through the one-pot reactions of ring-expansion of
Straightforward Stereoselective Synthesis of Seven-Membered Oxa-Bridged Rings through in Situ Generated Cycloheptenol Derivatives
Wang, Mengdan,Yin, Liqiang,Cheng, Lu,Yang, Yajie,Li, Yanzhong
, p. 12956 - 12963 (2021/09/13)
An iodine-mediated stereoselective synthesis of seven-membered oxa-bridged rings via in situ generated cycloheptenols was reported. This process was realized through the combination of C-C σ-bond cleavage and C-O bond-forming reactions in a one-pot fashion from simple and easily accessible raw materials. The formation of carbon radicals initiated by I2 was the key to the reaction.
Electrochemical Palladium-Catalyzed Oxidative Sonogashira Carbonylation of Arylhydrazines and Alkynes to Ynones
Cao, Yue,Hu, Jingcheng,Lei, Aiwen,Li, Haoran,Shi, Renyi,Wu, Yong,Xu, Minghao,Yi, Hong,Zeng, Li
supporting information, p. 12460 - 12466 (2021/08/24)
Oxidative carbonylation using carbon monoxide has evolved as an attractive tool to valuable carbonyl-containing compounds, while mixing CO with a stoichiometric amount of a chemical oxidant especially oxygen is hazardous and limits its application in scale-up synthesis. By employing anodic oxidation, we developed an electrochemical palladium-catalyzed oxidative carbonylation of arylhydrazines with alkynes, which is regarded as an alternative supplement of the carbonylative Sonogashira reaction. Combining an undivided cell with constant current mode, oxygen-free conditions avoids the explosion hazard of CO. A diversity of ynones are efficiently obtained using accessible arylhydrazines and alkynes under copper-free conditions. A possible mechanism of the electrochemical Pd(0)/Pd(II) cycle is rationalized based upon cyclic voltammetry, kinetic studies, and intermediates experiments.
One-Pot Palladium-Catalyzed Carbonylative Sonogashira Coupling using Carbon Dioxide as Carbonyl Source
Xiong, Wenfang,Wu, Bowen,Zhu, Baiyao,Tan, Xiaobin,Wang, Lu,Wu, Wanqing,Qi, Chaorong,Jiang, Huanfeng
, p. 2843 - 2851 (2021/05/10)
Carbonylation coupling reaction has emerged as a powerful and versatile strategy for the construction of carbonyl-containing compounds in modern synthetic chemistry over the past years. Carbon dioxide, a renewable one carbon molecule, has become one of the most attractive and promising alternative carbonyl sources due to its highly abundance, nontoxicity and stability in comparison with CO in recent years. However, in most cases, a two-chamber technique was generally necessary to allow the CO-producing and CO-consuming processes to perform successfully because of the complexities and incompatibility of reaction conditions, when carbon dioxide was utilized as carbonyl source. Herein, a practical one-pot protocol using carbon dioxide as the carbonyl source for the palladium-catalyzed carbonylative Sonogashira coupling has been established, providing an expedient and practical route to a wide range of functionalized alkynones and indoxyls under mild reaction conditions. By finding a suitable catalytic system, the method allowed the CO-generating and CO-consuming processes to proceed in one pot, wherein carbon monoxide was generated in situ from the reduction of carbon dioxide in the absence of any fluoride reagents. Simple and safe operation, readily available substrates, good functional group tolerance and mild reaction conditions are the features of the method.
Sc(OTf)3-catalyzed [3 + 2]-cycloaddition of nitrones with ynones
He, Chun-Ting,Han, Xiao-Li,Zhang, Yan-Xue,Du, Zhen-Ting,Si, Chang-Mei,Wei, Bang-Guo
supporting information, p. 457 - 466 (2021/01/29)
An efficient approach to access functionalized (2,3-dihydroisoxazol-4-yl) ketones has been developed by reacting nitrones 4 with ynones 7 or terminal ynones 10 in a one-pot fashion. The reaction went through a formal Sc(OTf)3-catalyzed [3 + 2]-cycloaddition process to generate a number of functionalized (2,3-dihydroisoxazol-4-yl) ketones 11aa-11aw, 11ba-11la and 12aa-12ae in moderate to good yields. This journal is
Synthesis of Isoselenazoles and Isothiazoles from Demethoxylative Cycloaddition of Alkynyl Oxime Ethers
Zhang, Zhu-Zhu,Chen, Rong,Zhang, Xiao-Hong,Zhang, Xing-Guo
, p. 632 - 642 (2020/12/22)
A general method for the synthesis of isoselenazoles and isothiazoles has been developed by the base-promoted demethoxylative cycloaddition of alkynyl oxime ethers using the cheap and inactive Se powder and Na2S as selenium and sulfur sources. This transformation features the direct construction of N-, Se-, and S-containing heterocycles through the formation of N-Se/S and C-Se/S bonds in one-pot reactions with excellent functional group tolerance.
Synthesis of 2-isoxazolyl-2,3-dihydrobenzofuransviapalladium-catalyzed cascade cyclization of alkenyl ethers
Zhou, Fei,Li, Can,Li, Meng,Jin, Yangbin,Jiang, Huanfeng,Zhang, Yingjun,Wu, Wanqing
supporting information, p. 4799 - 4802 (2021/05/25)
A novel palladium-catalyzed cascade cyclization reaction of alkenyl ethers with alkynyl oxime ethers for the construction of poly-heterocyclic scaffolds has been developed, in which the electron-rich alkene moiety functions as a three-atom unit, simultaneously dealing well with the coordination and regioselectivity of electron-rich olefins under metal catalysis. The strategy features excellent regio- and chemoselectivities as well as good functional group tolerance. Moreover, the newly formed 2-isoxazolyl-2,3-dihydrobenzofuran products can be further transformed to diverse complex heterocycles, demonstrating their potential applications in organic synthesis and medicinal chemistry.
Methylation Alkynylation of Terminal Alkenes via 1,2-Alkynyl Migration Using Dicumyl Peroxide as the Methyl Source
Qin, Yi-Qun,Chen, De,Liu, Liang,Zhang, Jia-Jia,Peng, Xin-Ju,Luo, Yong-Yue,Deng, Wei,Xiang, Jiannan
, p. 4700 - 4708 (2021/08/31)
The metal-free oxidative alkene methylation/alkynylation of 1,4-enyn-3-ols with an organic peroxide as the methyl source has been developed, which provides straightforward and practical access to the challenging quaternary-carbon-containing but-3-yn-1-one
Selective Insertion of Alkynes into C-C σ Bonds of Indolin-2-ones: Transition-Metal-Free Ring Expansion Reactions to Seven-Membered-Ring Benzolactams or Chromone Derivatives
Wang, Mengdan,Yang, Yajie,Song, Bo,Yin, Liqiang,Yan, Shuhui,Li, Yanzhong
supporting information, p. 155 - 159 (2020/01/03)
An unprecedented ring expansion reaction of indolin-2-ones with alkynyl ketones under transition-metal-free conditions has been developed. Base-promoted selective cleavage of a C-C σ bond of the amide is the key in this process, which provides a straightf
