2445-82-1Relevant academic research and scientific papers
A novel NHC-catalyzed transformation of 2H-chromene-3-carboxaldehydes to 3-methyl-2H-chromen-2-ones
Nair, Vijay,Sinu,Rejithamol,Seetha Lakshmi,Suresh, Eringathodi
, p. 5511 - 5514 (2011)
An unexpected transformation of 2H-chromene-3-carboxaldehydes to coumarin derivatives, mediated by NHC, is reported.
Efficient synthesis of 3-methyl-2H-chromen-2-one: Classic versus microwave conditions
Florekova, Lenka,Flasik, Radoslav,Stankovicova, Henrieta,Gaplovsky, Anton
, p. 1514 - 1519 (2011)
The reaction of salicylaldehyde with propionic anhydride in the presence of anhydrous K2CO3 as catalyst afforded 3-methyl-2H-chromen- 2-one (3-methylcoumarin) in good yields depending on the reaction conditions. The reaction was performed under classic thermal (55% yield) and microwave conditions (91-97% yield).
Copper(I)-Catalyzed 3-Position Methylation of Coumarins by Using Di-tert-butyl Peroxide as the Methylation Reagents
Zhuang, Huan,Zeng, Runsheng,Zou, Jianping
, p. 368 - 372 (2016)
The copper-catalyzed methylation of coumarin by using di-tert-butyl peroxide (DTBP) has been described. The reaction provides direct access to a wide range of 3-methylcoumarins in moderate to good yields. In this procedure, it is noteworthy that DTBP was employed not only as the oxidant, but also as the methyl source. The copper-catalyzed methylation of coumarin by using di-tert-butyl peroxide (DTBP) has been described. The reaction provides direct access to a wide range of 3-methylcoumarins in moderate to good yields. In this procedure, it is noteworthy that DTBP was employed not only as the oxidant, but also as the methyl source.
Facile Synthesis of 3-Methyl-5,6-dihydro-2H-pyran-2-ones and 3-Methylcoumarines under Mild Conditions
Falsone, Gioacchino,Spur, Bernd,Wingen, Peter H.
, p. 763 - 766 (1983)
The synthesis of the 3-methyl-5,6-dihydro-2H-pyran-2-one, 3, 5 and the 3-methylcoumarines 7a-e from the β-hydroxyoxo compounds 1,4,6a-c and the phosphonopropionic acid 2 under Wittig-Horner conditions is described.
Exploring Pd/Al2O3 Catalysed Redox Isomerisation of Allyl Alcohol as a Platform to Create Structural Diversity
Dékány, Attila,Lázár, Enik?,Szabó, Bálint,Havasi, Viktor,Halasi, Gyula,Sápi, András,Kukovecz, ákos,Kónya, Zoltán,Sz?ri, Kornél,London, Gábor
, p. 1834 - 1843 (2017)
Abstract: We report our results on exploiting the different reactivities present in the catalytic cycle of the Pd/Al2O3 catalyzed redox isomerization of allyl alcohol. We show that the reactivity of allyl alcohol derived acrolein and enol can be involved in further cascade reactions leading to a diverse set of products. While the oxidation product acrolein can react via Michael and oxa-Michael reactions, the isomerization product enol can be readily involved in aldol condensation processes. Salicylaldehydes, that are able to react on their electrophilic carbonyl and nucleophilic OH-groups with allyl alcohol derived enol and acrolein, respectively, are used to explore conditions where the structure of the product heterocycles can be controlled. Graphical Abstract: [Figure not available: see fulltext.].
Novel one-pot asymmetric cascade approach toward densely substituted enantioenriched α-methylene-γ-lactams
Tan, Yu,Yang, Xiao-Di,Liu, Wen-Jie,Sun, Xing-Wen
, p. 6105 - 6108 (2014)
A novel one-pot asymmetric synthesis of densely substituted α-methylene-γ-lactams in favor of cis-isomer involving Zn-promoted aza-Barbier-type reaction has been well established. A wide array of α-methylene-γ-lactams were obtained in high yields with excellent diastereomeric ratios from 98:2 to >99:1 and good enantioselectivities. The synthetic potential of such α-methylene-γ-lactams was demonstrated by successfully oxidizing the phenol moiety to quinone in quantitative yield.
Synthesis and properties of a new coumarin functionalized tetrathiafulvalene derivative
Hu, Liang,Zhu, Rong-Mei,Qin, Jie,Zhou, Xin-Hui
, p. 573 - 578 (2013)
Anew tetrathiafulvalene (TTF) derivative possessing Schiff base core with the coumarin moiety has been synthesized and characterized. The crystal structure has been studied, and the electrochemical and spectroscopic properties have also been investigated. Optimized conformation and molecular orbital diagram of the title compound have been calculated with density functional theory (DFT).
Visible-Light-Induced C(sp2)-C(sp3) Coupling Reaction for the Regioselective Synthesis of 3-Functionalized Coumarins
Li, Hanjie,Lin, Zhenwei,Lu, Ping,Qiao, Li,Wang, Yanguang,Xie, Jianwei,Zhang, Ke
, p. 9552 - 9562 (2021/07/26)
A photocatalysis strategy for the regioselective synthesis of 3-functionalized coumarins is reported. With visible light irradiation, a direct and regioselective C(sp2)-C(sp3) coupling reaction of 3-(2-hydroxyphenyl)acrylates with ethers or thioethers occurs by using Ru(bpy)3Cl2·6H2O as a photocatalyst and TBHP as an oxidant. The cascade process involves alkenylation of the C(sp3)-H bond of ethers and lactonization, furnishing 3-alkylated coumarins as the final products. This approach is characterized by a broad substrate scope, mild reaction conditions, and simplified operation. The synthesis of 3-alkylated coumarins could be realized by a one-pot procedure, starting from commercially available salicylaldehyde.
Visible-light promoted oxidative cyclization of cinnamic acid derivatives using xanthone as the photocatalyst
Zhao, Bin,Xu, Bo
supporting information, p. 568 - 573 (2021/02/06)
We have developed an efficient photocatalytic synthesis of coumarin derivativesviaa tandem double bond isomerization/oxidative cyclization of cinnamic acids. Inexpensive and stable xanthone was used as the photocatalyst, and readily available Selectfluor was used as the oxidant. This method tolerates a wide range of functional groups and offers excellent chemical yields in general. Besides, the photocatalytic oxidative cyclization of cinnamic acid esters gives dimerized lignan-type products.
Coumarins by Direct Annulation: β-Borylacrylates as Ambiphilic C3-Synthons
Wienhold, Max,Molloy, John J.,Daniliuc, Constantin G.,Gilmour, Ryan
supporting information, p. 685 - 689 (2020/11/30)
Modular β-borylacrylates have been validated as programmable, ambiphilic C3-synthons in the cascade annulation of 2-halo-phenol derivatives to generate structurally and electronically diverse coumarins. Key to this [3+3] disconnection is the BPin unit which serves a dual purpose as both a traceless linker for C(sp2)–C(sp2) coupling, and as a chromophore extension to enable inversion of the alkene geometry via selective energy transfer catalysis. Mild isomerisation is a pre-condition to access 3-substituted coumarins and provides a handle for divergence. The method is showcased in the synthesis of representative natural products that contain this venerable chemotype. Facile entry into π-expanded estrone derivatives modified at the A-ring is disclosed to demonstrate the potential of the method in bioassay development or in drug repurposing.
