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A transition metal-free strategy is reported for the site-selective O-arylation of cyclic 1,3-dicarbonyls with polyfluoroarenes. This method offers a straightforward and alternative pathway for the synthesis of aryl ethers, accommodating a wide array of functional groups. Furthermore, the practical value of this methodology is underscored by its facile scalability to gram-level reactions, its potential for diverse synthetic applications, and its aptitude for complex molecules modifications. [ABSTRACT FROM AUTHOR]

Synthesis of enol carbamates was achieved via nickel‐catalyzed oxidative coupling of formamides with 1,3‐dicarbonyl compounds in the presence of tert‐butyl hydroperoxide at 40 °C. Various derivatives of enol carbamates were synthesized by this method in good to excellent yields. [ABSTRACT FROM AUTHOR]

A facile and versatile catalyst-free method for the preparation of a wide range of pentasubstituted pyrroles has been reported using four-component reactions of arylglyoxal monohydrate, β- keto esters, amines, and various cyclic 1,3-dicarbonyls under mild reaction conditions. Employing this methodology, pseudo sevencomponent reactions have also been achieved in the case of p-phenylenediamine to provide conjugated bispyrroles with arene spacers. [ABSTRACT FROM AUTHOR]

A novel, convenient, and efficient three-component reaction of benzoin derivatives, 1,3-dicarbonyls, and ammonium acetate in the presence of silica sulfuric acid (SSA) is described for the synthesis of 2,3,4,5-tetrasubstituted pyrroles under solvent-free conditions. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes new and efficient synthetic approaches for biologically interesting tetrahydroquinoline analogues. The key strategies involve the ethylenediamine diacetate-catalyzed cyclization of 1,3-dicarbonyls to aminobenzaldehydes through domino Knoevenagel/hetero Diels–Alder reactions. These reactions provide a rapid route for the synthesis of novel polycycles with the tetrahydroquinoline moiety. [Copyright &y& Elsevier]

Abstract: Various 1,3-dicarbonyl compounds reacted readily with benzylic and propargylic alcohols in the presence of 10mol% of phosphomolybdic acid supported on silica gel (PMA/SiO2) under mild reaction conditions to produce 2-benzylic- and 2-propargylic-1,3-dicarbonyl compounds in excellent yields and with high selectivity. [Copyright &y& Elsevier]

Abstract: Glycals undergo smooth coupling with β-enaminoketones and β-enaminoesters generated in situ from 1,3-dicarbonyl compounds and arylamines in the presence of 10mol% of InCl3 in refluxing dichloroethane to produce oxa-aza bicyclononene scaffolds in excellent yields with high selectivity. The use of InCl3 makes this protocol simple, convenient and easy to scale-up. [Copyright &y& Elsevier]

Abstract: In this present paper, we report the efficient, regioselective one-pot synthesis of 5-alkoxy and 5-alkylsulfanylpyrrole-3-carboxylates in high yields via the zinc perchlorate-catalyzed addition of alcohols and thiols to the nitrile carbon of α-cyanomethyl-β-ketoesters followed by annulation. The addition–annulation process is undertaken in aqueous solution to give 4,5-dihydro-5-oxo-1H-pyrrole-3-carboxylates (pyrrolinones) in good yields. These 4,5-dihydro-5-oxo-1H-pyrrole-3-carboxylates are also obtained by the hydrolysis of 5-alkoxypyrrole-3-carboxylates. [Copyright &y& Elsevier]

Abstract: In this paper, we report the efficient and regioselective synthesis of 2-aminopyrrole-4-carboxylates as derivatives of conformationally restricted analogues of γ-amino butyrates (GABA) via a zinc perchlorate catalyzed amination–annulation of α-cyanomethyl-β-ketoesters under mild reaction conditions in water. [Copyright &y& Elsevier]

Abstract: Efficient syntheses of 2-aminopyrroles are presented starting from β-dicarbonyl compounds, bromoacetonitrile, and amines. Alkylation of β-dicarbonyl compounds with bromoacetonitrile furnished α-cyanomethyl-β-dicarbonyl compounds. The condensation reaction of α-cyanomethyl-β-dicarbonyl compounds with amines catalyzed by p-TsOH affords the corresponding enamines in good yields. Base catalyzed cyclization via the addition of an amine moiety to the carbon–nitrogen triple bond of nitrile furnished 2-aminopyrroles in high yields. [Copyright &y& Elsevier]

1-Substituted 1,2,3,4-tetrahydroisoquinoline systems were prepared by reaction of cotarnine with the NH-and CH-acids methyl- and acyl derivatives of pyrazole and 1,3-dicarbonyl reagents. Depending on the structure and reaction conditions, bifunctional pyrazole nucleophiles can give substitution products at the N atom, methyl, or acyl group; 1,3-diketones, at the terminal methyl. Rearrangements occurring during the reaction of cotarnine with bifunctional substrates were studied. [ABSTRACT FROM AUTHOR]

Abstract: A hydroxyapatite-bound La complex, which functioned as an efficient heterogeneous catalyst for the Michael reaction of 1,3-dicarbonyls with enones under aqueous or solvent-free conditions, was prepared using a cation-exchange method. Further application to an asymmetric version by a fluoroapatite-bound La complex catalyst modified with (R,R)-tartaric acid is also described. [Copyright &y& Elsevier]

Abstract: Poly-substituted dihydrofurans and tetrahydrofurans have been synthesized through polymer-supported selenium-induced intramolecular electrophilic cyclization, followed by selenoxide syn-elimination or novel nucleophilic substitution cleavage of selenium resin with good yields and purities. [Copyright &y& Elsevier]

A revelation: Enamine activation of α‐branched β‐ketocarbonyl compounds is actually possible, very efficient, and highly enantioselective with a bifunctional primary amine/tertiary ammonium triflate salt catalyst. This covalent HOMO activation mode competes with existing strategies for the enantioselective activation of β‐ketocarbonyls and their analogues. E=Electrophile; X=CH2, O, NR; OTf=Triflate. [ABSTRACT FROM AUTHOR]