41786-36-1

Upstream product

• 19115-30-1 1-(4-methoxyphenyl)-2-propyn-1-ol 
• 108-95-2 phenol 
• 1666-14-4 N’-(2-hydroxybenzylidene)-4-methylbenzene-1-sulfonohydrazide 
• 768-60-5 4-methoxyphenylacetylen 
• 254-04-6 2H-chromene 
• 100-66-3 methoxybenzene 
• 118-93-4 o-hydroxyacetophenone 
• 123-11-5 4-methoxy-benzaldehyde 
• 90-02-8 salicylaldehyde 
• 6303-59-9 (E)-4-(2-bromo-vinyl)-anisole 
• 1963-36-6 4-methoxycinnamaldehyde 
• 88284-48-4 2-(trimethylsilyl)phenyl trifluoromethanesulfonate 
• 5720-07-0 4-methoxyphenylboronic acid 
• 98-80-6 phenylboronic acid 

Downstream Products

• 90878-08-3 2-[(E)-1-Ethyl-3-(4-methoxy-phenyl)-allyl]-phenol 
• 4143-74-2 4'-methoxyflavone 
• 88214-90-8 2-hydroxy-4'-methoxy-α,β-dihydrochalcone 
• 1261361-45-8 2-(4-methoxyphenyl)-2H-chromene 
• 1255509-72-8 (R)-2-(4-methoxyphenyl)-2H-chromene 
• 53388-68-4 2,3-cis-3,4-trans-4-acetoxy-3-bromo-4'-methoxyflavan 
• 89840-25-5 2,3-trans-3,4-trans-4-p-methoxyphenoxy-4'-methoxyflavan-3-ol 
• 89840-25-5 2,3-trans-3,4-cis-4-p-methoxyphenoxy-4'-methoxyflavan-3-ol 
• 89840-23-3 2,3-trans-3,4-trans-4-p-tolyloxy-4'-methoxyflavan-3-ol 
• 89840-23-3 2,3-trans-3,4-cis-4-p-tolyloxy-4'-methoxyflavan-3-ol 
• 89840-21-1 2,3-trans-3,4-trans-4-phenoxy-4'-methoxyflavan-3-ol 
• 53388-75-3 2,3-trans-4'-methoxyflav-3-ene epoxide 

Relevant academic research and scientific papers

Transition-Metal-Free Cross-Coupling of Indium Organometallics with Chromene and Isochroman Acetals Mediated by BF3·OEt2

A transition-metal-free coupling of triorganoindium reagents with benzopyranyl acetals mediated by a Lewis acid has been developed. The reaction of R3In with chromene and isochroman acetals in the presence of BF3·OEt2 afforded 2-substituted chromenes and 1-substituted isochromans, respectively, in good yields. The reactions proceed with a variety of triorganoindium reagents (aryl, heteroaryl, alkynyl, alkenyl, alkyl) using only 50 mol % of the organometallic, thus demonstrating the efficiency of these species. Preliminary mechanistic studies indicate the formation of an oxocarbenium ion intermediate in the presence of the Lewis acid.

Indium-catalyzed oxidative cross-dehydrogenative coupling of chromenes with 1,3-dicarbonyls and aryl rings

An effective indium-catalyzed oxidative cross-dehydrogenative coupling of electronically varied chromenes with 1,3-dicarbonyl compounds and aryl rings has been established. Both the C-H alkylation and arylation proceed smoothly at room temperature to affo

Intramolecular etherification and polyene cyclization of π-Activated Alcohols Promoted by Hot Water

Hot water, acting as a mildly acidic catalyst, efficiently promoted intramolecular direct nucleophilic substitution reactions of unsaturated alcohols with heteroatom or carbon nucleophiles. In a mixed solvent of water and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), polyene cyclizations using allylic alcohols as initiators gave the desired cyclized products, and in neat HFIP, a tricyclization reaction gave a tetracyclic product in 51% chemical yield.

Design, synthesis and biological activity of flavonoid derivatives as selective agonists for neuromedin U 2 receptor

Central neuromedin U 2 receptor (NMU2R) plays important roles in the regulation of food intake and body weight. Identification of NMU2R agonists may lead to the development of pharmaceutical agents to treat obesity. Based on the structure of rutin, a typi

Structurally diverse α-substituted benzopyran synthesis through a practical metal-free C(sp3)-H functionalization

A trityl ion-mediated practical C-H functionalization of a variety of benzopyrans with a wide range of nucleophiles (organoboranes and C-H molecules) at ambient temperature has been disclosed. The metal-free reaction has an excellent functional group tole

Palladium-catalyzed coupling of N-tosylhydrazones and β-bromostyrene derivatives: New approach to 2H-chromenes

2H-Chromene is an important structural motif that exists in natural products and non-natural compounds possessing interesting biological activities. In this investigation, a highly efficient approach toward 2H-chromenes has been developed based on palladium-catalyzed coupling of N-tosylhydrazones and β-bromostyrenes. The mechanism of this reaction is proposed that involves the formation of vinyl palladium by carbene migratory insertion and the intramolecular nucleophilic substitution. This journal is

Metalloradical approach to 2H -chromenes

Cobalt(III)-carbene radicals, generated through metalloradical activation of salicyl N-tosylhydrazones by cobalt(II) complexes of porphyrins, readily undergo radical addition to terminal alkynes to produce salicyl-vinyl radical intermediates. Subsequent hydrogen atom transfer (HAT) from the hydroxy group of the salicyl moiety to the vinyl radical leads to the formation of 2H-chromenes. The Co(II)-catalyzed process can tolerate various substitution patterns and produces the corresponding 2H-chromene products in good isolated yields. EPR spectroscopy and radical-trapping experiments with TEMPO are in agreement with the proposed radical mechanism. DFT calculations reveal the formation of the salicyl-vinyl radical intermediate by a metalloradical-mediated process. Unexpectedly, subsequent HAT from the hydroxy moiety to the vinyl radical leads to formation of an o-quinone methide intermediate, which dissociates spontaneously from the cobalt center and easily undergoes an endocyclic, sigmatropic ring-closing reaction to form the final 2H-chromene product.

An unexpected rearrangement-hydration reaction sequence of 2H-chromenes to dihydrochalcones under catalysis of HAuCl4

2-Aryl-2H-chromenes in aqueous DCM medium under catalysis of HAuCl 4 are converted into 3-(2-hydroxyaryl)-1-arylpropan-1-ones through hydration-rearrangement reaction sequence in very good yield. The key step probably involves the [1,5] hydride shift followed by the hydrolysis under the reaction condition. The notable advantages of this method are operational simplicity and ease of isolation of products and also provide a pathway to convert the chalcone into DHCs with the transposition of carbonyl group. 2012 Elsevier Ltd. All rights reserved.

A facile synthesis of 2h-chromenes and 9-functionalized phenanthrenes through reactions between α,β-unsaturated compounds and arynes

Facile syntheses of 2H-chromenes or 9-functionalized phenanthrenes under mild conditions in moderate to good yields have been developed. They each involve annulations of arynes with α,β-unsaturated compounds bearing different electron-withdrawing groups (EWGs). Depending on the natures of the different EWGs, the reactions proceed by different pathways: enals react with arynes through a tandem [2+2] cycloaddition/thermal electrocyclic ring-opening/6e-electrocyclization sequence to afford 2H-chromenes, whereas acyl-/ethoxycarbonyl-/cyano-substituted styrenes undergo Diels-Alder reactions with arynes followed by aromatization to afford 9-functionalized phenanthrenes. The scope, limitations, regioselectivities and mechanisms have been studied and are discussed in detail. Depending on the natures of different EWGs in α,β-unsaturated compounds, the reactions between arynes and α,β-unsaturated compounds proceed by different tandem pathways to afford either 2H-chromenes or 9-functionalized phenanthrenes in a selective manner, which is of potential pharmaceutical interest.

Nickel-catalyzed cross-coupling of chromene acetals and boronic acids

A modular and highly efficient protocol for the synthesis of 2-aryl- and heteroaryl-2H-chromenes is described. Under base-free conditions, readily accessible 2-ethoxy-2H-chromenes undergo Csp3-O activation and C sp3-C bond formation in the presence of an inexpensive nickel catalyst and boronic acids. This new strategy enables broad access to 2-substituted-2H-chromenes and has been applied to the late-stage incorporation of complex molecules, including the pharmaceuticals loratidine and indomethacin methyl ester.