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A multicomponent synthesis of 3,4-disubstituted N-aminopyrrolidine-2,5-diones is described. A mixture of N-isocyaniminotriphenylphosphorane, an aldimine and Meldrum's acid undergoes an addition reaction under mild conditions in aqueous THF to produce 1-amino-4-aryl-2,5-dioxo-N³-aryl-3-pyrrolidinecarboxamides diastereoselectively in good to excellent yields. ±H NMR analysis showed that the two substituents on C-3 and C-4 positions of the obtained pyrrolidine-2,5-diones are trans. [ABSTRACT FROM AUTHOR]

Some new amidated fentanyl (= N-[1-(2-phenylethyl)piperidin-4-yl]- N-phenylpropanamide) analogs with a 4-( N-phenylamido)piperidine scaffold and additional amide bonds have been designed and synthesized through Ugi four-component reaction ( Ugi-4CR). Good-to-high yields, diversity-oriented synthesis, and possible applications in drug discovery are advantages of this approach. [ABSTRACT FROM AUTHOR]

Abstract: An efficient method for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles from isothiocyanates and hydrazides through cyclodesulfurization in the presence of (O-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate) TBTU as an uronium coupling reagent has been developed. The present methodology offers several advantages, such as simple and easy work-up procedures, mild reaction conditions and it is environmentally benign. [Copyright &y& Elsevier]

A simple synthesis of N2-alkyl- N3-[2-(1,3,4-oxadiazol-2-yl)aryl]benzofuran-2,3-diamines 5 via a one-pot four-component reaction is described ( Scheme 1). A mixture of N-(isocyanoimino)triphenylphosphorane ( 1), a 2-aminobenzoic acid 2, a 2-hydroxybenzaldehyde 3, and an isocyanide 4 in absolute EtOH at room temperature undergoes a smooth reaction to afford 5 in excellent yields ( Table). [ABSTRACT FROM AUTHOR]

Abstract: A concise and facile synthesis of a new class of P,O-heterocycles is described. Knoevenagel condensation reaction of a salicylaldehyde and a cyclohexane-1,3-dione forms an α,β-unsaturated intermediate, which undergoes nucleophilic addition of a trialkyl phosphite under solvent-free conditions to afford the title compounds in good to excellent yields. [Copyright &y& Elsevier]

Abstract: An efficient method for the stereoselective synthesis of 3-(diarylmethylene)-2-oxindoles and 3-(arylmethylene)-2-oxindoles via carbopalladation is described. In this approach, an Ugi-4-component reaction (4-CR) adduct was used as the starting material. A one-pot sequence involving intermolecular carbopalladation C–H activation/C–C bond formation efficiently afforded the oxindole derivatives. [Copyright &y& Elsevier]

Abstract: An efficient strategy for the one-pot syntheses of indolo[1,2-a]quinoxalinones catalyzed by CuI have been developed. The procedures combine the Ugi four-component reaction of aldehydes, 2-iodoaniline, 2-indole carboxylic acid, and isocyanides followed by the copper-catalyzed intramolecular N-arylation of the Ugi product in one-pot procedure, which afford the desired products in good to very good yields. [Copyright &y& Elsevier]

Abstract: The three-component reaction of primary amines, dialkyl acetylenedicarboxylates and β-nitrostyrene derivatives in the presence of Iron(III) chloride afforded 1,2,3,4-tetra-substituted pyrroles in high yields. These reactions could precede via domino Michael addition/cyclization process. [Copyright &y& Elsevier]

Abstract: An efficient palladium-catalyzed protocol for the stereoselective synthesis of 3-(aminoarylmethylene)-oxindoles has been developed. In this approach, Ugi-4-component reaction adducts were used as starting materials for carbopalladative cyclization–Buchwald reaction sequences. [Copyright &y& Elsevier]

Abstract: Potentially bioactive 3-(anilinoarylmethylene)-2-oxindoles as Hesperadin analogoues have been synthesized via a two-step procedure: (a) an Ugi-4MCR and (b) reaction of the Ugi adduct with aniline in the presence of a palladium catalyst via domino Heck/Buchwald reaction. In all cases, a single isomer with the Z-configuration was obtained in good to high yields. [Copyright &y& Elsevier]

Abstract: A multi-component synthesis of 3-aryl-1-(arylmethylideneamino)pyrrolidine-2,5-diones is described. A mixture of N-isocyaniminotriphenylphosphorane, an aldehyde, and Meldrum''s acid undergo a 1:2:1 addition reaction under mild conditions to afford the title compounds in good to excellent yields. [Copyright &y& Elsevier]

Abstract: Trifluoroethanol was used as a reusable catalyst and medium for the ring opening of epoxides using aliphatic and aromatic amines as nucleophile under mild conditions to give the corresponding β-amino alcohols in high yields and regioselectivity. [Copyright &y& Elsevier]

Abstract: Hantzsch 1,4-dihydropyridine, polyhydroquinoline and 1,8-dioxodecahydroacridines derivatives were synthesized in excellent yields in trifluoroethanol (TFE). The solvent (TFE) can be readily separated from reaction products and recovered in excellent purity for direct reuse. [Copyright &y& Elsevier]

Abstract: A simple synthesis of benzo[d,e]imidazo[2,1-a]isoquinolines is described. Heating a mixture of acenaphthoquinone, a benzil, and ammonium acetate under solvent-free conditions afforded 9,10-diaryl-7H-benzo[d,e]imidazo[2,1-a]isoquinolin-7-ones in good to excellent yields. [Copyright &y& Elsevier]

Abstract: Polyfunctional 1,4-disubstituted piperazines were successfully synthesized stereoselectively via a one-pot, five-component Ugi/nucleophilic addition reaction sequence. Regio- and stereo-selective addition of piperazine to an activated alkyne under catalyst-free conditions and high yields of products are advantages of this method. [Copyright &y& Elsevier]

Abstract: A novel and one-pot synthesis of 2-aryl/alkyl-4(3H)-quinazolinones is described. The in situ prepared amidoximes from the reaction between nitriles and hydroxylamine are condensed with anthranilic acids under solvent- and catalyst-free conditions to produce the title compounds in excellent yields. [Copyright &y& Elsevier]

Abstract: A novel synthesis of 5-(alkylamino)-4-aryl-3-isoxazolecarboxamides is described. Heating a mixture of an isocyanide and a nitrostyrene in water afforded the title compounds in excellent yields. [Copyright &y& Elsevier]

A facile protocol allows the synthesis of the title phosphonates from 2-formylbenzoic acid, amines, and trialkylphosphite at room temperature under catalyst- and solvent-free conditions. [ABSTRACT FROM AUTHOR]