175276-69-4

Upstream product

• 72771-97-2 ethyl 2-acetyl-4-(4-nitrophenyl)-4-oxobutanoate 
• 41780-82-9 4-methyl-N'-(1-(4-nitrophenyl)ethylidene)benzenesulfonohydrazide 
• 141-97-9 ethyl acetoacetate 
• 100-19-6 (4-nitrophenyl)ethanone 
• 2009-97-4 ethyl 2-diazo-3-oxobutanoate 
• 74812-79-6 1-(4-nitrophenyl)-1-trimethylsilyloxyethylene 

Downstream Products

• 175276-70-7 ethyl 5-(4-aminophenyl)-2-methyl-3-furanecarboxylate 

Relevant academic research and scientific papers

Copper-Mediated [3 + 2] Oxidative Cyclization Reaction of N-Tosylhydrazones and β-Ketoesters: Synthesis of 2,3,5-Trisubstituted Furans

The first attempt at utilizing N-tosylhydrazones as two-carbon synthons has been successfully achieved, which underwent a copper-mediated [3 + 2] oxidative cyclization reaction to afford 2,3,5-trisubstituted furans in moderate to good yields. The features of this method include inexpensive metal catalyst, readily available substrates, high regioselectivity, and convenient operation. The studies provide important approaches for further exploration of the powerful and diverse reaction abilities of N-tosylhydrazones.

Copper-Catalyzed Coupling of 2-Siloxy-1-alkenes and Diazocarbonyl Compounds: Approach to Multisubstituted Furans, Pyrroles, and Thiophenes

We report herein copper(II)-catalyzed cyclization reactions of silyl enol ethers derived from methyl ketones with α-diazo-β-ketoesters or α-diazoketones to afford 2-siloxy-2,3-dihydrofuran derivatives or 2,3,5-trisubstituted furans, respectively, under mild conditions. The former cyclization products serve as versatile 1,4-diketone surrogates, allowing facile preparation of 2,3,5-trisubstituted furans, pyrroles, and thiophenes.

Ionic liquid as catalyst and reaction medium: A Simple and Efficient Procedure for Paal-Knorr furan synthesis

The ionic liquid 1-butyl-3-methyl-imidazolium hydrogen sulfate, [bmim]HSO4, efficiently catalyzes Paal-Knorr furan synthesis without any organic solvent. A wide range of aliphatic and aromatic 1,4-diketones easily undergo condensations to form furan derivatives, providing a general and convenient procedure. The Paal-Knorr reaction of ester-substituted 1,4-diketones is first reported. The ionic liquid can be recovered and reused for subsequent runs without any appreciable loss of efficiency.