14071-69-3

Upstream product

• 622-47-9 4-tolylacetic acid 
• 90-02-8 salicylaldehyde 
• 91-64-5 coumarin 
• 98-59-9 p-toluenesulfonyl chloride 
• 108-88-3 toluene 
• 623-13-2 4-methylphenyl methylsulfide 
• 1333483-18-3 N-methyl-N-(p-tolylethynyl)methanesulfonamide 
• 106-49-0 p-toluidine 
• 99-94-5 p-Toluic acid 
• 766-97-2 4-n-methylphenylacetylene 
• 50978-45-5 3-oxobenzo[d]isothiazole-2(3H)-carbaldehyde 1,1-dioxide 
• 104-82-5 4-Methylbenzyl chloride 
• 531-81-7 2-oxo-2H-chromene-3-carboxylic acid 
• 5720-05-8 4-methylphenylboronic acid 

Downstream Products

• 59583-83-4 4-(2-oxo-2H-chromen-3-yl)benzaldehyde 
• 1337918-42-9 C₄₆H₄₁BF₂N₄O₂ 
• 1337918-41-8 C₄₄H₃₅BF₂N₂O₄ 

Relevant academic research and scientific papers

Direct C-3 alkylation of coumarins via decarboxylative coupling with carboxylic acids

A new method for selective C-3 alkylation of coumarins using carboxylic acids as alkyl sources is reported. This process offers a practical method for the facile construction of 3-alkyl coumarins with a broad substrate scope. The reaction works under metal-free and aqueous media and both cyclic and acyclic aliphatic carboxylic acids participate in this radical C-C cross coupling reaction.

Chlorophyll-catalyzed photochemical regioselective coumarin C-H arylation with diazonium salts

This communication describes the development of a mild method for the cross-coupling of the C3-position of coumarin with an array of diazonium salts mediated by chlorophyll as a biocatalyst via visible light catalysis. A natural pigment such as chlorophyll is used as a green photosensitizer and environmentally benign catalyst. This general and easy procedure provides a transition-metal-free alternative for the formation of 3-aryl coumarin derivatives at room temperature with good to excellent yields. This journal is

Facile one-pot synthetic access to libraries of diversely substituted 3-aryl (Alkyl)-coumarins using ionic liquid (IL) or conventional base/solvent, and an IL-mediated approach to novel coumarin-bearing diaryl-ethynes

The in-situ formed carbonylimidazole derivatives of Ar(alkyl)-CH2COOH react at r.t. with substituted salicylaldehydes in [BMIM][PF6] or [BMIM][BF4] as solvent, and [PAIM][NTf2] as basic-IL, to produce libraries of 3-aryl(alkyl)coumarins. Whereas these reactions can also be performed with similar efficiency in THF by employing DBU, the IL approach offers easier work-up and recycling of the IL solvent. An IL-mediated approach to the synthesis of novel coumarin-bearing diaryl-ethynes by the Sonogshira reaction is also reported, and the potential for recycling/reuse of the IL solvent is shown.

Zn(II)-Catalyzed One-Pot Synthesis of Coumarins from Ynamides and Salicylaldehydes

A highly efficient and straightforward synthesis of diversely substituted coumarins from ynamides and salicylaldehydes in the presence of Zn(II) catalyst has been developed. The sulfonamide moiety of ynamides was successfully recycled in this process, serving as an effective traceless directing group for high regioselectivity in the bond-forming event. The advantages of this protocol are good functional group tolerance, broad substrate scope, simple and high-yielding reaction, recovery/reuse of the sulfonamides, low catalyst loading of inexpensive catalyst, and, by these merits, a more cost-effective and greener process.

Visible-light-driven copper-catalyzed aerobic oxidative cascade cyclization of N-tosylhydrazones and terminal alkynes: Regioselective synthesis of 3-arylcoumarins

We present the first example of sustainable, intuitive, highly regioselective, visible-light-driven copper catalyzed aerobic oxidative cascade cyclization of N-tosylhydrazones with terminal alkynes for the preparation of 3-arylcoumarins at room temperature. This operationally simple methodology has been successfully applied to a wide range of N-tosylhydrazones and alkynes (49 examples), and proceeds well to afford biologically active compounds, such as monoamine oxidase B (MAO-B) inhibitor and horseradish peroxidase (HRP) inhibitor, in satisfactory yields under mild conditions. Furthermore, mechanistic studies suggest that the reaction proceeds via a copper(ii)-superoxo or -peroxo complex mediated oxidative annulation of terminal alkynes, as evidenced by 18O2 isotopic-labelling experiments.

Rational design of slightly twisted coumarin molecules with remarkable solution and solid dual efficient luminescence

Endowing slightly twisted molecules highly emissive in both solution and solid state is of great importance for understanding the principle of maximizing the luminescent efficiency of luminophores. To this end, a series of slightly twisted coumarin luminophores CMs with different alkoxyl substituents at the 7-positions were synthesized. The effect of the substitutes on the diversity photophysical properties of the four compounds in solution, THF/H2O mixtures and solid state were investigated. Comparing to the referenced compound CM (3-p-tolyl-2H-chromen-2-one) that without a substitute, the introduced electron-rich alkoxyl substitutes not only enhanced the intramolecular charge transfer (ICT) effect, but also significantly modified their molecular packing patterns in the crystals. The combined effect of increasing the radiative and suppressing the nonradiactive pathways boosted the luminescence efficiency of CM1-CM3 in solution and the solid state simultaneously. Eventually, compound CM2 with an ethoxyl substitute exhibited the strongest blue emission with fluorescence quantum yields as high as 73.2% and 96.7% in solution and the solid state, respectively. This work presents an efficient strategy towards dual strong fluorescent luminophores in both solution and the solid state.

Pd-catalysed carbonylative annulation of salicylaldehydes with benzyl chlorides using N-formylsaccharin as a CO surrogate

A convenient and highly efficient Pd-catalysed carbonylative annulation of salicylaldehydes with benzyl chlorides to afford the corresponding 3-arylcoumarins in good to excellent yields has been developed. Importantly, the protocol utilizes a commercially available, low cost, solid and easy to handle N-formylsaccharin as an alternative to the highly toxic CO gas.

A transition-metal-free fast track to flavones and 3-arylcoumarins

A highly regioselective and transition-metal free one-pot arylation of chromenones with arylboronic acids has been achieved employing K2S2O8. The procedure consists of a sequence of some reactions including an arylation/decarboxylation cascade and proceeds well in aqueous media to afford biologically interesting flavones and 3-arylcoumarins. This method exhibited excellent selectivity and functional group tolerance under mild conditions. The reaction also showed perfect efficacy for the preparation of styryl coumarins.

KMnO4/AcOH-mediated C3-selective direct arylation of coumarins with arylboronic acids

An efficient protocol for KMnO4/AcOH-mediated dehydrogenative direct radical arylation of coumarins with arylboronic acids to afford 3-arylcoumarin derivatives is described. A similar reaction system is also applicable to the 3-arylation of quinolinone derivatives. These KMnO4/AcOH-mediated coupling reactions occur regioselectively at the C3 position of coumarins and quinolinones. Some notable features of this method are high efficiency, moderate to good yield, and a broad group tolerance.

Regioselective α-arylation of coumarins and 2-pyridones with phenylhydrazines under transition-metal-free conditions

A facile regioselective metal-free direct α-arylation of coumarins and 2-pyridones is achieved by the reaction of coumarins and 2-pyridones with phenylhydrazine in good yields. The reaction proceeds at room temperature under mild conditions using inexpensive reagents and without the need for step intensive activating groups. The methodology is operationally simple, practically viable and also allows the coupling of similar nitrogen heterocycle aza-coumarins without prerequisite N-protection.