1230-48-4

Upstream product

• 15982-64-6 1,4-bis(4-methoxyphenyl)butane-1,4-dione 
• 104-92-7 1-bromo-4-methoxy-benzene 
• 17113-31-4 2-(4-methoxyphenyl)furan 
• 121239-89-2 1,4-bis (4-methoxyphenyl)-2-butyne-1,4-dione 
• 15331-49-4 trans-1,2-di(4-methoxybenzoyl)ethylene 
• 63366-23-4 2,5-bis(trimethylstannyl)furan 
• 93298-06-7 2-bromo-1-(4-methoxy-phenyl)-ethanone semicarbazone 
• 93298-11-4 C₂₀H₂₄N₆O₄ 
• 2632-13-5 2-Bromo-4'-methoxyacetophenone 
• 543692-18-8 2,5-bis(n-butyltellanyl)furan 
• 1145987-18-3 (1E,3E)-1-methoxy-1,4-bis(4-methoxyphenyl)buta-1,3-diene 
• 22779-05-1 1,4-bis(4-methoxyphenyl)-1,3-butadiyne 
• 84132-74-1 2-(4-methoxyphenyl)-2,5-dihydrofuran 
• 309723-10-2 1-(1-allyloxyallyl)-4-methoxybenzene 

Relevant academic research and scientific papers

Intermediates in the Paal-Knorr Synthesis of Furans

New experimental evidence for the mechanism of the Paal-Knorr reaction involving the acid-catalyzed cyclization of a 1,4-diketone to form a furan is reported.In aqueous or alcoholic solutions containing hydrochloric acid and in chloroform containing boron trifluoride-etherate d,l- and meso-3,4-diethyl-2,5-hexanediones (2r and 2m) cyclize at unequal rates; the stereochemical configuration of the unchanged dione is preserved during the reaction.This disagrees with commonly accepted mechanism involving the ring closure of the rapidly formed monoenol (11b) followed by loss of water.A pathway involving the rapid protonation of one of the carbonyls followed by the electrophilic attack on the protonated carbonyl by the enol being formed at the other carbonyl group (10c) is proposed to account for the difference in reaction rates between the diastereomers of 3,4-disubstituted 2,5-hexanediones (1-3).The following results also seem to support the intermediacy of 10c.The presence of two isopropyl groups in 3,4-diisopropyl-2,5-hexanedione (3) considerably reduces the rate of cyclization.The catalytic constants kH(+) for the cyclization of 2r and 2m are larger than the constants for enolization of methyl ketones.The diastereomers of 2,3-dimethyl- and 2,3-diethyl-1,4-diphenyl-1,4-butanediones (4 and 5), which could enolize only toward the center of the molecule, also react at different rates.The d,l and meso dideuterio analogs (d2-4r and d2-4m) exhibit a primary isotope effect during cyclization.The order of cyclization of 1,4-diphenyl-1,4-butanedione (6) and its analogs (7-9) reveals that the presence of electron-donating groups facilitate the reaction.

Copper-impregnated magnetite as a heterogeneous catalyst for the homocoupling of terminal alkynes

Copper-impregnated magnetite is a versatile heterogeneous catalytic system for the synthesis of 1,3-diynes by the homocoupling of terminal alkynes. This catalyst does not require the use of pressurized oxygen as the oxidant and it does not need a solvent or harsh conditions to give the expected products. Moreover, the catalyst can be removed from the reaction medium simply by using a magnet. The reaction occurs at the lowest copper loading reported for any heterogeneous catalyst.

Facile microwave-mediated transformations of 2-butene-1,4-diones and 2-butyne-1,4-diones to furan derivatives

Several di- and triarylfuran derivatives were prepared in high yields from but-2-ene-1,4-diones/but-2-yne-1,4-diones using formic acid in the presence of a catalytic amount of palladium on carbon and in poly(ethylene glycol)-200 medium in a one-pot operation under microwave irradiation (1-5 min).

Synthesis and?evaluation of?cytotoxic activity of?arylfurans

A series of 2-aryl and 2,5-diarylfurans were synthesized and evaluated for their in vitro cytotoxicity against human cancer cells lines and on the proliferation of human peripheral blood mononuclear cells (PBMC) stimulated with phytohemaglutinin (PHA). Three compounds were found to present significant activity against the cancer cell lines without affecting the lymphocyte proliferation in PBMCs, indicating low toxicity to normal cells.

Aryl(triethyl)silanes for Biaryl and Teraryl Synthesis by Copper(II)-Catalyzed Cross-Coupling Reaction

Aryl(triethyl)silanes are found to undergo cross-coupling with iodoarenes in the presence of catalytic amounts of CuBr2and Ph-Davephos, as well as cesium fluoride as a stoichiometric base. Because the silicon reagents are readily accessible through catalytic C?H silylation of aromatic substrates, the net transformation allows coupling of aromatic hydrocarbons with iodoarenes via triethylsilylation.

Visible-Light Induced Direct Synthesis of Polysubstituted Furans from Cyclopropyl Ketones

In this article, a photoredox protocol for the synthesis of furans via oxidative coupling of olefin generated in situ from cyclopropyl ketones with ketonic oxygen atom is presented. Moreover, bromination of furans in the presence of overstoichiometric oxidant has been achieved with high regioselectivity.

Copper(II)-Promoted, One-Pot Conversion of 1-Alkynes with Anhydrides or Primary Amines to the Respective 2,5-Disubstituted Furans or Pyrroles under Microwave Irradiation Conditions

Furans and pyrroles are prepared from 1-alkynes by using a Cu(II)-promoted, one-pot, microwave irradiation method. Glaser coupling of 1-alkynes and cyclization of the resulting 1,3-diyne in the presence of an anhydride or a primary amine results in the formation of the respective 2,5-diaryl- or 2,5-dialkyl-substituted furans and pyrroles.

Copper-catalyzed direct synthesis of furans and thiophenes via decarboxylative coupling of alkynyl carboxylic acids with H2O or Na2S

2,5-Diaryl-substituted furans were synthesized from the copper-catalyzed decarboxylative coupling of aryl-substituted aryl propiolic acids in the presence of H2O. The homocoupling of alkynyl carboxylic acids provided 1,4-diaryldiynes, which then reacted with H2O to give the desired furans through cyclization. Addition of the copper catalyst was critical, and the addition of a ligand increased the yield of products in both the homocoupling and cyclization reactions. In addition, thiophenes could be obtained when the reaction was conducted in the presence of Na2S.

Gold-catalyzed formation of C-O and C-C bonds: An efficient domino reaction synthesis of functionalized furans

An efficient gold-catalyzed domino reaction for the synthesis of furan derivatives from haloalkynes has been described. This transformation has provided a new route for the formation of C-O and C-C bonds that prepare functionalized furans.

A general approach to arylated furans, pyrroles, and thiophenes

A general and practical synthetic method for aryl-substituted five-membered heterocycles has been developed. In the presence of KOH (30%), 1,4-diaryl-1,3-butadiynes undergo the cyclocondensation reaction with water, primary amines, and Na2S·9H2O in DMSO at 80 °C to afford 2,5-diarylfurans, 1,2,5-trisubstituted pyrroles, and 2,5-diarylthiophenes in good to high yields. Further studies have disclosed that aryl-substituted five-membered heterocycles can be also synthesized by a one-pot, two-step strategy from the terminal alkynes in DMSO firstly catalyzed by CuCl, and then via addition of KOH to promote the cyclocondensation of 1,3-butadiynes generated in situ.