17372-52-0Relevant academic research and scientific papers
Orthoamides and iminium salts, CIV. Reactions of alkynecarboxylic acid orthoamides with enolizable CH2-acidic compounds and subsequent reactions of some of the condensation products
Edelmann, Kai,Frey, Wolfgang,Kantlehner, Willi,Mezger, Jochen,Vettel, Markus
, p. 417 - 430 (2021/08/26)
Orthoamides of alkynecarboxylic acid 15 condense with enolisable β-dicarbonyl compounds and as well with acetophenones to give 3-acryl-1,1-bis(dimethyl-amino)-1,3-butadienes. Some acylbutadienes cyclize affording 2-pyranon-derivatives 33 upon heating with
Synthetic Access to gem-Difluoropropargyl Vinyl Ethers and Their Application to Propargyl Claisen Rearrangement
Okamura, Toshitaka,Koyamada, Kenta,Kanazawa, Junichiro,Miyamoto, Kazunori,Iwabuchi, Yoshiharu,Uchiyama, Masanobu,Kanoh, Naoki
, p. 1911 - 1924 (2020/12/23)
With the increasing importance of fluorine to medicinal chemistry and other areas, methods to access various fluorinated compounds are needed. Herein, we report the synthesis of difluoropropargyl vinyl ethers from ketones and aldehydes using difluoropropargyl bromide dicobalt complexes. We applied difluoropropargyl vinyl ethers to the synthesis of difluorodienone or difluoroallene under thermal conditions and trifluoro-pyran under acid-catalyzed conditions.
Method for organic catalytic synthesis of 2-pyrone compound
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Paragraph 0029-0035, (2020/04/06)
The invention relates to a preparation method for rapidly constructing and synthesizing a 2-pyrone derivative containing a pyrone compound under the catalysis of N-heterocyclic carbene. The 2-pyrone derivative has the general structural formula described
Regioselective Synthesis of 5-Metalated 2-Pyrones by Intramolecular Oxymetalation of Carbonyl-ene-yne Compounds Using Indium Trihalide
Yata, Tetsuji,Kita, Yuji,Nishimoto, Yoshihiro,Yasuda, Makoto
, p. 14330 - 14341 (2019/11/03)
The oxyindation of carbonyl-ene-yne compounds with indium trihalides proceeded efficiently to give di-, tri-, and tetrasubstituted 2-pyrones bearing a carbon-indium bond. The metalated 2-pyrone and a zwitterion intermediate were identified by X-ray crystallographic analysis. The application of organoindium compounds to oxidation or cross-coupling provided easy access to various multifunctionalized 2-pyrones. Some 2-pyrone derivatives show intense fluorescence only in the solid state (aggregation-induced emission).
Unexpected reactivity of pyridinium salts toward alkynyl Fischer complexes to produce oxo-heterocycles
Flores-Conde, María Inés,de la Cruz, Fabiola N.,López, Julio,Jiménez-Halla, J. óscar C.,Pe?a-Cabrera, Eduardo,Flores-álamo, Marcos,Delgado, Francisco,Vázquez, Miguel A.
, (2017/12/28)
The unprecedented reaction of ketone-containing aromatic pyridinium salts 3a-e and alkynyl Fischer complexes 1a-f proceeds via a mild domino process to provide 4,6-disubstituted pyran-2-ones 5a-k and 2,3,5-trisubstituted furans 6a-h (45-97%). According of the results of isotopic labeling experiments, a mechanism involving an initial Michael addition appears to be the key step, obtaining a mesomeric structure responsible for the formation of both products.
N-Heterocyclic Carbene-Catalyzed Annulation of Ylides with Ynals: Direct Access to α-Pyrones
Lang, Ming,Jia, Qianfa,Wang, Jian
supporting information, p. 2427 - 2430 (2018/09/10)
We herein report an N-Heterocyclic Carbene (NHC)-catalyzed annulation of ylides with ynals that provides an efficient protocol to make 4,6-disubstituted α-pyrones. This method affords a variety of α-pyrones in good to high yields as well as broad substrat
Synthesis of α-pyrones by catalytic oxidative coupling of terminal alkynes and carbon dioxide
Oliveros-Cruz, Saray,Arévalo, Alma,García, Juventino J.
, p. 18 - 22 (2017/01/10)
The use of the complex [(dippe)Ni(μ-H)]2(1) as a catalyst precursor (10?mol%) in the presence of a variety of terminal alkynes and CO2allowed the production of substituted α–pyrones. This reaction occurs using relatively mild conditions (50?°C, 150 psi of CO2) with good to modest yields, depending on the nature of the substituents in the corresponding alkyne. The produced α–pyrones were characterized by different analytical methods and spectroscopic techniques.
Preparation of 4,6-Disubstituted α-Pyrones by Oxidative N-Heterocyclic Carbene Catalysis
Bera, Srikrishna,Studer, Armido
, p. 121 - 126 (2016/12/24)
An efficient synthesis of 4,6-disubstituted α-pyrones employing redox activation of enals using N-heterocyclic carbene catalysis is reported. The strategy uses aroyl-substituted nitromethanes and enals as substrates and reactions proceed through an additi
A novel abnormal michael reaction of 2-Acylmethyl-4,4-dimethyl-2-oxazolines with acetylenic ketones and Esters
Tohda, Yasuo,Yanagidani, Takeshi,Asaka, Noriko
, p. 810 - 822 (2016/08/02)
The first example of abnormal Michael reaction of an active methylene compound, 2-acylmethyl-4,4-dimethyl-2-oxazoline with acetylenic ketone in acetonitrile is reported. The reaction accompanies 1,3-migration of the acyl group of the substrate to give 2-(3-acyl-1-buten-4-on-1-yl)-2-oxazoline, which was easily cyclized to 5-acyl-2-pyridone derivatives by treatment with silica gel. Selectivity of the reaction depends on bulkiness of all the substituents of both the substrate and the reagent. The selectivity is interpreted in terms of reduced kinetic acidity of an initial anionic adduct intermediate by both steric and electronic factors.
Carboxylative cyclization of substituted propenyl ketones using CO2: Transition-metal-free synthesis of Α-pyrones
Zhang, Wen-Zhen,Yang, Ming-Wang,Lu, Xiao-Bing
supporting information, p. 4181 - 4184 (2016/08/02)
Carbon dioxide is a green carboxylative reagent due to its non-toxic and renewable properties. Described herein is a carboxylative cyclization of substituted 1-propenyl ketones via γ-carboxylation using CO2, which provides an efficient, transit
