39180-26-2Relevant academic research and scientific papers
Synthesis of Highly Substituted Biaryls by the Construction of a Benzene Ring via in Situ Formed Acetals
Balamurugan, Rengarajan,Manojveer, Seetharaman,Tarigopula, Chandrahas
, p. 11871 - 11883 (2021/09/13)
Herein, we present an interesting method for the construction of a benzene ring using propargylic alcohols and 1,3-dicarbonyls, which involves three new C-C bond formations via cascade alkylation, formylation, annulation, and aromatization to make substituted biaryls. This one-pot Br?nsted acid-promoted protocol utilizes the unique reactivity of the acetal formed under the reaction conditions. Alkynyl methyl ketones could be employed instead of 1,3-dicarbonyls as they are converted to 1,3-dicarbonyls by hydration under the reaction conditions.
Synthesis method of aryl-substituted alkyne
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Paragraph 0031; 0049-0050, (2021/10/20)
The invention relates to the technical field of synthesis of aryl substituted alkyne, and discloses a synthetic method of an aryl-substituted alkyne, and discloses a synthesis method of an aryl-substituted alkyne. Aryl boronic acid and divalent copper compounds, 8 - hydroxyquinoline, an oxidizing agent and an inorganic base are added to the reaction solvent, and the aryl substituted alkyne is obtained by stirring and separating after stirring at room temperature. Compared with the existing sonogashira reaction, the synthesis method disclosed by the invention realizes the aryl reaction of the lean electron alkyne through the oxidative coupling reaction, avoids Sonogashira reaction required precious palladium catalyst, can react at room temperature, and is mild in reaction condition and high in product yield.
Synthesis of substituted benzo[: B] [1,4]oxazepine derivatives by the reaction of 2-aminophenols with alkynones
Oshimoto, Kohei,Zhou, Biao,Tsuji, Hiroaki,Kawatsura, Motoi
supporting information, p. 415 - 419 (2020/01/30)
We have developed a novel synthetic method accessing benzo[b][1,4]oxazepines that are one of the rare classes of benzoxazepine derivatives by reaction of 2-aminophenols with alkynones in 1,4-dioxane at 100 °C. A series of benzo[b][1,4]oxazepine derivatives can be prepared by using this synthetic protocol. Mechanistic experiments indicated that the hydroxy proton of the aminophenol could play a crucial role in the formation of an alkynylketimine intermediate that undergoes 7-endo-dig cyclization.
Phosphine-Catalyzed Intermolecular Annulations of Fluorinated ortho-Aminophenones with Alkynones – The Switchable [4+2] or [4+2]/[3+2] Cycloaddition
Zhang, Yanshun,Sun, Yaoliang,Wei, Yin,Shi, Min
supporting information, p. 2129 - 2135 (2019/03/13)
A phosphine-catalyzed intermolecular annulation reaction of functionalized ortho-aminoacetophenones with alkynones has been disclosed in this paper. A variety of 2-alkynylquinolines and benzo-fused indolizine were selectively afforded in moderate to good yields at different reaction temperatures and with different phosphine catalysts via the in situ generated zwitterionic intermediate derived from alkynone and phosphine. (Figure presented.).
Enantioselective Cyanosilylation of Alkynyl Ketones Catalyzed by Combined Systems Consisting of Chiral Ruthenium(II) Complex and Lithium Phenoxide
Ohkuma, Takeshi,Kurono, Nobuhito,Sakaguchi, Yusuke,Yamauchi, Kohei,Yurino, Taiga
, p. 1517 - 1522 (2018/02/28)
Asymmetric cyanosilylation of alkynyl ketones with the catalyst systems consisting of amino acid/2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP)/ruthenium(II) complex and lithium phenoxide (Ru?Li cat.) was studied. The reaction was conducted in tert-butyl methyl ether (TBME) at ?78 °C with a substrate-to-catalyst molar ratio (S/C) as high as 2000. A series of simple and functionalized ketones was converted into the alkynyl tertiary cyanohydrin derivatives in up to 99% ee. Appropriate selection of an amino-acid ligand of the catalyst according to the substrate structure was crucially important to achieve high enantioselectivity and a wide scope of substrates. Transformation of the chiral cyanohydrin product into a functionalized lactone was also examined. (Figure presented.).
Iridium-Catalyzed Asymmetric Transfer Hydrogenation of Alkynyl Ketones Using Sodium Formate and Ethanol as Hydrogen Sources
Zhang, Yang-Ming,Yuan, Ming-Lei,Liu, Wei-Peng,Xie, Jian-Hua,Zhou, Qi-Lin
supporting information, p. 4486 - 4489 (2018/08/09)
A green and efficient iridium-catalyzed asymmetric transfer hydrogenation of alkynyl ketones to chiral propargylic alcohols has been developed. By using sodium formate and ethanol as hydrogen sources, a series of alkynyl ketones were hydrogenated by chira
Highly efficient synthesis of benzodioxins with a 2-site quaternary carbon structure by secondary amine-catalyzed dual Michael cascade reactions
He, Xuefeng,Li, Yongsu,Wang, Meng,Chen, Hui-Xuan,Chen, Bin,Liang, Hao,Zhang, Yaqi,Pang, Jiyan,Qiu, Liqin
supporting information, p. 5533 - 5538 (2018/08/12)
Salicylic acids and substituted ynones were employed as substrates to afford a class of valuable 4H-benzo[d][1,3]dioxin-4-ones with a 2-site quaternary carbon structure in up to 92% yield by secondary amine-catalyzed dual Michael cascade reactions under mild reaction conditions. The α,β-unsaturated ketone as the key intermediate in the cascade process was successfully separated and characterized. As a result, a new reaction route for ynone species is demonstrated, which is totally different from the existing allenamine activation model.
Gold-catalyzed Fluorination of Alkynyl Esters and Ketones: Efficient Access to Fluorinated 1,3-Dicarbonyl Compounds
Zeng, Xiaojun,Lu, Zhichao,Liu, Shiwen,Hammond, Gerald B.,Xu, Bo
, p. 4062 - 4066 (2017/11/30)
We developed an efficient synthesis of 2-fluoro-1,3-dicarbonyl compounds using readily available alkynyl ketones or esters as starting material. The key step is the insertion of hydrogen fluoride (HF) to the gold carbene intermediate generated from cationic gold catalyzed addition of N-oxides to alkynyl ketones or esters. This method gives excellent chemical yields and regioselectivity with good functional group tolerance. (Figure presented.).
Phosphane-Catalyzed [3+3] Annulation of C,N-Cyclic Azomethine Imines with Ynones: A Practical Method for Tricyclic Dinitrogen-Fused Heterocycles
Li, Zhen,Yu, Hao,Liu, Yang,Zhou, Leijie,Sun, Zhanhu,Guo, Hongchao
supporting information, p. 1880 - 1885 (2016/07/06)
A phosphane-catalyzed [3+3] annulation of azomethine imines with ynones has been developed. Under mild reaction conditions, the reaction proceeds smoothly to afford tricyclic dinitrogen-fused heterocyclic compounds in moderate to excellent yields with moderate to excellent stereoselectivies. Using a chiral phosphine as the catalyst, the reaction could work to give the cycloadduct in moderate yield with moderate enantioselectivity. (Figure presented.) .
Aerobic oxidation of propargylic alcohols to αβ,-unsaturated alkynals or alkynones catalyzed by fe(NOH, TEMPO and sodium chloride in toluene
Liu, Jinxian,Xie, Xi,Ma, Shengming
experimental part, p. 1569 - 1576 (2012/06/30)
A practical aerobic oxidation of propargylic alcohols using Fe(NOH, TEMPO and sodium chloride in toluene at room temperature was applied to various type of propargylic alcohols affording ,-unsaturated alkynals or alkynones in good to excellent yields. This protocol could be applied in academic laboratories as well as in industrial-scale production.
