125155-08-0

Upstream product

• 100-52-7 benzaldehyde 
• 125155-04-6 diethyl [(2-oxo-2H-chromen-3-yl)methyl]phosphonate 
• 28321-12-2 (E)-(4,4-difluorobuta-1,3-diene-1-yl)benzene 
• 90-02-8 salicylaldehyde 
• 531-81-7 2-oxo-2H-chromene-3-carboxylic acid 
• 4363-35-3 Dihydroxy-styryl-boran 
• 6783-05-7 trans-2-phenylvinylboronic acid 
• 100-42-5 styrene 
• 99851-57-7 3-vinyl-2H-benzopyran-2-one 
• 591-50-4 iodobenzene 
• 108-86-1 bromobenzene 
• 1017553-99-9 2-formylphenyl but-3-enoate 
• 125155-02-4 2-Formylphenyl 3-(diethoxyphosphoryl)propionate 
• 939-18-4 3-bromo-2H-chromen-2-one 

Relevant academic research and scientific papers

Palladium-catalyzed cross-coupling reaction of diazo compounds and vinyl boronic acids: An approach to 1,3-diene compounds

A palladium-catalyzed oxidative cross-coupling of vinyl boronic acids and cyclic α-diazocarbonyl compounds has been reported. The reaction constitutes an efficient method for the synthesis of 1,3-diene compounds bearing a ring structure. Mechanistically, the reaction involves migratory insertion of palladium carbene as the key step.

Bulky Selenium Ligand Stabilized Trans-Palladium Dichloride Complexes as Catalyst for Silver-Free Decarboxylative Coupling of Coumarin-3-Carboxylic Acids

This report describes the syntheses of three new trans-palladium dichloride complexes of bulky selenium ligands. These complexes possess a Cl?Pd?Cl rotor spoke attached to a Se?Pd?Se axle. The new ligands and palladium complexes (C1?C3) were characterized with the help of NMR, HRMS, UV-Vis., IR, and elemental analysis. The single-crystal structure of metal complex C2 confirmed a square planar geometry of complex with trans-orientation. The X-ray structure revealed intramolecular secondary interactions (SeCH—Cl) between chlorine of PdCl2 and CH2 proton of selenium ligand. Variable-temperature NMR data shows coalescence of diastereotopic protons, which indicates pyramidal inversion of selenium atom at elevated temperature. The relaxed potential energy scan of C2 suggests a rotational barrier of ～12.5 kcal/mol for rotation of chlorine atom through Cl?Pd?Cl rotor. The complex C3 possesses dual intramolecular secondary interactions (OCH2—Cl and SeCH2—Cl) with stator ligand. Molecular rotor C2 was found to be a most efficient catalyst for the decarboxylative Heck-coupling under mild reaction conditions. The protocol is applicable to a broad range of substrates with large functional group tolerance and low catalyst loading (2.5 mol %). The mechanism of decarboxylative Heck-coupling reaction was investigated through experimental and computational studies. Importantly the reaction works under silver-free conditions which reduces the cost of overall protocol. Further, the catalyst also worked for decarboxylative arylation and decarboxylative Suzuki-Miyaura coupling reactions with good yields of the coupled products.

Synthesis of 2,2-Difluorinated 4-Isoflavanols/4-Thioisoflavanols via a Base-Catalyzed [4 + 2] Annulation Reaction of gem-Difluoroolefins

DBU-catalyzed sequential intermolecular and intramolecular nucleophilic addition reactions between gem-difluoroolefins and o-hydroxy/mercapto benzaldehydes have been developed to provide a [4 + 2] annulation strategy for facile synthesis of gem-difluorinated isoflavanol derivatives. The competitive addition-elimination reaction of gem-difluoroolefins with nucleophiles was avoided under mild conditions, affording 2,2-difluorinated 4-isoflavanols or 2,2-difluoriated 4-thioisoflavanols in good to excellent yields.

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.

Palladium-catalyzed decarboxylative cross-coupling reactions: A route for regioselective functionalization of coumarins

A straightforward, regioselective, and step-economical ligand-free palladium-catalyzed decarboxylative functionalization of coumarin-3-carboxylic acids is devised. This protocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allows for construction of various biologically important π-electron extended coumarins.

Convenient synthesis of 3-vinyl and 3-styryl coumarins

A variety of 2-hydroxy aldehydes on reaction with 3-butenoic acid afford in a one-pot reaction the corresponding 3-vinylcoumarins. As expected, extension of the delocalized π-electron system accomplished by Heck coupling reactions with aryl halides results in an increased fluorescence of the compounds whose applicability is yet to be established.

Single-compound libraries of organic materials: Parallel synthesis and screening of fluorescent dyes

"Hits" with high quantum yields: The screening of the chromophores of a coumarin library for optical properties allowed the identification of "hits" with high fluorescence quantum yields (see picture) which could be used as fluorescence labels and laser dyes. The generation of the library was facilitated by an efficient method involving the parallel synthesis utilizing Pd-catalyzed cross-coupling reactions.

A Convenient Horner-Emmons Approach to the Synthesis of Substituted Ethyl 1,3-Butadiene-2-carboxylates, and Related Compounds

The Horner-Emmons reaction of the allylphosphonates 3 with aldehydes gives substituted 1,3-butadiene-2-carboxylates 12 in satisfactory yields.By suitable modification of reactants a variety of 3-alkenyl-2(5H)-furanones 13 and 3-alkenylcoumarins 14 are pre