Synthesis of functionalized 5-imino-2,5-dihydro-furans through the reaction of isocyanides with activated acetylenes in the presence of ethyl bromopyruvate

Summary The reaction between alkyl(aryl) isocyanides and dibenzoylacetylene in the presence of ethyl bromopyruvate leads to ethyl 3,4-dibenzoyl-2-bromomethyl-5-alkyl(aryl)imino-2,5-dihydro-furan-2-carboxylates in high yields. Dialkyl acetylenedicarboxylates react with tert-butyl isocyanide and ethyl bromopyruvate to produce 3,4-dialkyl 2-ethyl 2-bromomethyl-5-tert-butylimino-2,5-dihydro-furan-2,3,4-tricarboxylates.     

Isocyanide‐based three‐component synthesis of functionalized 5‐alkylimino‐2,5‐dihydrofuran‐3,4‐dicarboxylate and their conversion to substituted furanones

The zwitterionic 1:1 intermediates formed from alkyl isocyanides and acetylenic esters are trapped by alkyl bromides to form 5‐alkylimino‐2,5‐dihydrofuran‐3,4‐dicarboxylate in relatively good yields at room temperature under solventless conditions. Hydrolysis of these compounds by HCl (5%) produced substituted furanones. J. Heterocyclic Chem., (2011).     

Solvent‐free synthesis of pyrrole derivatives

A one‐pot synthesis of pyrrole derivatives via reaction between activated carbonyl compounds, primary amines, and 1,3‐dicarbonyls under solvent‐free conditions is described. J. Heterocyclic Chem., (2012).     

Four-component green synthesis of benzochromene derivatives using nano-KF/clinoptilolite as basic catalyst: study of antioxidant activity

Molecular Diversity - An efficient procedure for the synthesis of benzochromene derivatives employing 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone (euparin), aldehydes, alkyl bromides,...     

Multicomponent reactions for the synthesis of functionalized 1, 4-oxathiane-3-thiones under microwave irradiation in water

A series of substituted 1,4-oxathiane-3-thione derivatives were synthesized via one-pot multicomponent reactions of nitromethane, carbon disulfide and oxiranes in the presence of Et3N in water as the solvent under microwave irradiation. Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and straightforward procedure.     

Synthesis and Dynamic NMR Study of a Functionalized Sulfonamide Phosphonate Diester

Abstract

Protonation of the highly reactive 1:1 intermediate produced in the reaction between triphenylphosphite and activated acetylene by sulfonamide leads to a phosphonate ylide, which undergoes methanol elimination in the presence of moisture to produce a highly functionalized sulfonamide phosphonate diester. A dynamic nuclear magnetic resonance (NMR) effect is observed in the ¹H NMR spectra of this compound as a result of restricted rotation around the single C?N bond. The coalescence temperature was observed at T_C = 352.5 K, and the free energy of activation (ΔG^#) for this process is 75.6 ± 2 kJ.mol^?1.

GRAPHICAL ABSTRACT     

A Simple Synthesis of Oxaphospholes

Abstract

Stable derivatives of oxaphospholes were obtained from the reaction between electron-deficient acetylenic compounds and phenacyl bromide or its derivatives in the presence of triphenylphosphine in acetonitrile as the solvent in excellent yields.

GRAPHICAL ABSTRACT     

Efficient synthesis of 2,3,4-trisubstituted furans from the reaction of activated acetylenes with ethyl bromopyruvate in the presence of enaminones

The reaction of dialkyl acetylenedicarboxylates or diaroylacetylenes with ethyl bromopyruvate in the presence of enaminones led to 2-ethyl 3,4-dialkyl 4-bromo-4,5-dihydro-2,3,4-furantricarboxylates or ethyl 3,4-diaroyl-4-bromo-4,5-dihydro-2-furancarboxylate in excellent yields. These compounds are quantitatively converted to the corresponding 2,3,4-trisubstituted furans by 4-dimethylaminopyridine. Correspondence: Issa Yavari, Chemistry Department, Tarbiat Modares University, PO Box 14115-175, Tehran, Iran.     

Solvent-free synthesis of substituted fve membered heterocycles: One-pot reaction of primary amine and alkyl propiolate or isothiocyanate in the presence of oxalyl chloride简

A novel, convenient and efficient approach to the synthesis of pyrrole and imidazole derivatives via the reaction between primary amines, alkyl propiolates or isothiocyanate and oxalyl chloride is described. The method offers several advantages including high yields of products and performing reaction under solvent-free conditions.