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Ferric dodecyl sulfonate [Fe(DS)3] is easily prepared and can be used as a Lewis acid surfactant catalyst in water to conduct the highly efficient electrophilic substitution reaction of indoles with aliphatic or aromatic aldehydes at room temperature. [ABSTRACT FROM AUTHOR]

The conjugate addition reactions of indoles with quinones were catalyzed efficiently by molecular iodine under ultrasonic irradiation to afford 3-indolylquinones in good to excellent yields, which provided a novel, mild, convenient approach for the preparation of 3-indolylquinones. [ABSTRACT FROM AUTHOR]

The conjugate addition reactions of amines with 1,4-naphthoquinone were catalyzed efficiently by molecular iodine under ultrasonic irradiation to afford 2-amino-1,4-naphthoquinones in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

A novel method for the Michael reaction of indoles to α,β-unsaturated ketones catalyzed by acidic ionic liquid is reported. We obtained the corresponding products in excellent yields in the presence of [hmim]HSO4. Development of this method has resulted in a new protocol for the synthesis of β-indolylketones. [ABSTRACT FROM AUTHOR]

The article focuses on the used of chiral CuI Tol-BINAP catalyst for the addition of Grignard regeants to α,Β-unsaturated esters in high regio- and enantioselectivities. The chiral catalyst has been synthesized and isolated. The excess of the chiral Tol-BINAP to CuI is important to obtain the product with high enantioselectivities. Secondary Grignard reagent works well to afford the product in excellent enantioselectivity.

The title compound, C20H11N3O4, was synthesized by one-pot reaction of isatin, malononitrile and 4-hydroxycoumarin in water. In the title molecule, the angle between the pyran plane and the indole ring system with a common spiro C atom is 88.23 (8)°. The molecules are linked into a three-dimensional framework by the formation of moderate N—H...O and N—H...N hydrogen bonds. [ABSTRACT FROM AUTHOR]

Chemoselective 2-isocyanoethylindole-based domino reactions for the construction of polycyclic spiroindoline derivatives and polysubstituted pyrroles have been developed. The reaction of 2-isocyanoethylindoles and gem-diactivated olefins lead to the polycyclic spiroindoline derivatives (up to 92% yields) in EtOH under reflux conditions. Furthermore, the three-component reaction of 2-isocyanoethylindoles with gem-diactivated olefins and secondary amines afford polysubstituted pyrroles (in moderate yields) in CH3CN under reflux conditions. [ABSTRACT FROM AUTHOR]

A novel catalyst-free one-pot tandem reaction for the stereoselective construction of polycyclic spiroindolines was developed. This method offers a straightforward access to structurally diverse polycyclic spiroindoline derivatives in high yields (up to 90%) with excellent levels of diastereoselectivity. [ABSTRACT FROM AUTHOR]

A simple and efficient approach to the synthesis of a novel series of polysubstituted 6′-(1H-indol-3-yl)-1′,7′-dihydrospiro[indoline-3,4′-pyrazolo[3,4-b]pyridine]-2-one derivatives in high yields was developed from a one-pot, three-component reaction of 3-cyanoacetyl indoles, isatins, and 1H-pyrazol-5-amines in H2O/HOAc. [ABSTRACT FROM AUTHOR]

All efficient one-pot synthesis of 4,5,6-triaryl-3,4-dihydropyrimidin-2( I H)-ones via a three-component Biginelli-type condensalion of;tldehyde, 2-phenylacetophenone, and urea/thiourea in the presence of a catalytic amounl of t-BuOK (20 mol %) is described. The reactions proceeded efficiently at 70°C to afford the desired products in moderate to good yields. Detailed mechanistic study shows that the Biginelli-type reaction using urea and thiourea proceeds through two totally different pathways. Enone 5 and bis-urea 8 were highly suggested as respective reaction intermediates for reactions involving thiourea and urea as substrates, [ABSTRACT FROM AUTHOR]

An intriguing new Wacker-type oxidation of alkynes catalyzed by PdBr2and CuBr2is described, which opens an efficient access to 1,2-diketones using molecular oxygen. Under the optimized conditions, a variety of alkynes, including diarylalkynes, arylalkylalkynes, and dialkylalkynes, were compatible substrates in this transformation. The mechanism of this reaction was preliminarily investigated by control experiments. [ABSTRACT FROM AUTHOR]

In this paper, a Cu(II)/Ag(I)-catalyzed cascade reaction of anthranils with sulfonylhydrazone to construct 2-phenyl-3-sulfonyl disubstituted quinoline derivatives under mild conditions was studied. The mechanism study indicated that this reaction involves radical addition, and new C-C, C-N, and C-S bonds were constructed in one step. [ABSTRACT FROM AUTHOR]

A novel and efficient approach for the selenium functionalization of indoles was developed with selenium powder as the selenium source, catalyzed by 2,2,6,6-tetramethylpiperidinooxy (TEMPO) and employing O2 as the green oxidant. This protocol provides a practical route for the synthesis of 3-selenylindole derivatives and has the advantages of readily available starting materials, mild reaction conditions, and a wide scope of substrates. Electron spin-resonance (ESR) studies reveal that the approach involves the formation of nitrogen-centered radicals and selenium radicals via oxidation of in situ generated selenoates. [ABSTRACT FROM AUTHOR]

A new and facile approach toward highly functionalized carbamimidoseleknoates was developed through the copper(I)-catalyzed ligand-promoted four-component reaction of isocyanides, selenium, amines, and aryl iodides. The reaction constructed a range of organoselenium compounds containing an isoselenourea skeleton with potential bioactivity directly from selenium powder. The simplicity of method and broad diversity of substrates also highlight this work. [ABSTRACT FROM AUTHOR]

A transition-metal-free process for the synthesis of unsymmetrical aryl sulfides via dual C-S bond formation by a one-pot three-component reaction of alcohols, organohalides, and odorless sodium thiosulfate in water has been developed. In addition, the aryl sulfides could also be prepared by the reaction of the corresponding alcohols and Bunte salts under the identical conditions. This protocol provides a green and efficient manner for the construction of various unsymmetrical aryl sulfides. [ABSTRACT FROM AUTHOR]

A Pd-catalyzed insertion and cycloaddition of CO2 and isocyanide into 2-iodoanilines under atmospheric pressure has been developed and affords quinazoline-2,4(1H,3H)-diones through the formation of new C-C, C-O, and C-N bonds under mild conditions. This reaction provides a new and practical method not only for the construction of quinazoline-2,4(1H,3H)-diones but also for the efficient utilization of carbon dioxide. [ABSTRACT FROM AUTHOR]

A Co(II)-catalyzed isocyanide insertion reaction with sulfonyl azides in alcohols to form sulfonyl isoureas via nitrene intermediate has been developed. This protocol provides a new, environmentally friendly, and simple strategy for the synthesis of sulfonyl isourea derivatives by employing a range of substrates under mild conditions. [ABSTRACT FROM AUTHOR]

A novel silver-catalyzed fluorination reaction of carbonyl directed alkynes in the presence of N-fluorobenzenesulfonimide and water with high regioselectivities has been developed. The established protocol provides an alternative method for rapid assembly of α-fluoroketone derivatives under simple and mild reaction conditions. The reaction pathway involves a ring closure and opening process for the construction of new C-O and C-F bonds. In addition, a fluorine-containing indanone was observed through further N-heterocyclic carbene catalyzed intramolecular crossed-benzoin reaction of α-fluoroketone. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed cascade arene/alkyne annulation reaction for the synthesis of fluorene-benzoxazine derivatives is developed. This transformation involves a 6-exo-dig cyclization, a 1,3-oxazine vinylpalladium intermediate, and a C-H bond activation. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed intramolecular Heck reaction and aminopalladation of N-(2-(1-phenylvinyl)phenyl)aniline for the efficient synthesis of dihydroindeno[1,2,3-kl]acridines and 3-arylindoles via tuning of the phosphine ligands and solvents under two optimized conditions are reported. The reaction follows a 1,4-Pd migration, aminopalladation, C(sp2)-H activation, as well as five- and six-membered-ring fusion to form different products. The dihydroindeno[1,2,3-kl]acridine derivatives showed higher triplet energy (ET) levels than common blue phosphorescent dopant and may serve as good host candidates for blue triplet emitters. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed tandem C-Br/C-H functionalization and cyclization of alkenes with organohalides is reported. This reaction provides an operationally simple method for the synthesis of various fluorene, pyrroloindole, and benzoxazine derivatives, which are useful pharmaceutical framework and photoelectronic devices. Two new C-C/O bonds, a quaternary carbon center and a new ring, are simultaneously formed in this one-pot reaction. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed tandem C-Br/C-H functionalization and cyclization of alkenes with organohalides is reported. This reaction provides an operationally simple method for the synthesis of various fluorene, pyrroloindole, and benzoxazine derivatives, which are useful pharmaceutical framework and photoelectronic devices. Two new C-C/O bonds, a quaternary carbon center and a new ring, are simultaneously formed in this one-pot reaction. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 2-substituted indene-1,3(2H)-diones from stable and readily available 1-(2-halophenyl)-1,3-diones by employing phenyl formate as a CO source has been developed. The reaction occurred via palladium-catalyzed intramolecular carbonylative annulation using K3PO4 as a base and DMSO as a solvent at 95 °C. In this protocol, the reaction showed a broad substrate scope with good to excellent yields. [ABSTRACT FROM AUTHOR]

A novel and efficient strategy for the synthesis of sterically hindered 4-amino-3-acyl-2-naphthols through a palladium-catalyzed coupling reaction involving isocyanide chemselective insertion and domino isomerization has been developed. The methodology, which is in accordance with the principle of "atom and step economy", efficiently constructs 4-amino-3-acyl-2-naphthols in moderate to good yields. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed efficient C-H acylation reaction of biaryl-2-amines and aromatic aldehydes is developed. This dehydrogenative cross-coupling protocol could furnish monoacylation and diacylation products in moderate to good yields with a broad substrate scope and good regioselectivity. [ABSTRACT FROM AUTHOR]

A novel synthetic approach toward 1,4-disubstituted 1,2,3-triazoles and 1,5-disubstituted 1,2,3-triazoles by aerobic oxidative cycloaddition of a-chlorotosylhydrazone with primary aryl amine has been developed. Significantly, the reaction proceeds smoothly to afford 1,4-disubstituted 1,2,3-triazoles and 1,5-disubstituted 1,2,3-triazoles under catalyst-free, metal-free, azide-free, and peroxide-free conditions. [ABSTRACT FROM AUTHOR]

An I2/CHP-mediated cross-coupling reaction of isocyanides with readily accessible amines via C-N formation is described for carbodiimide synthesis in moderate to excellent yields. This represents a metal-free strategy for a coupling reaction of isocyanides with amines, and it provides an efficient approach for symmetric and unsymmetric functionalized carbodiimide derivative synthesis under mild conditions. [ABSTRACT FROM AUTHOR]

Mn(III)-mediated reactions of 2-isocyanobiaryls with 1,3-dicarbonyl compounds were described for the construction of 6-alkylated and 6-monofluoro-alkylated phenanthridines in moderate to good yields. The reaction involves formation of two new C-C bonds and one C-C bond cleavage. [ABSTRACT FROM AUTHOR]

A metal-free method for direct C(sp³)-H bond functionalization of simple ethers with α,α-diaryl allylic alcohols is described. The established protocol provides facile access to α-aryl-β-oxyalkylated carbonyl ketones via radical addition and a 1,2-aryl migration cascade process. An application of the product has been demonstrated in the synthesis of a serotonin antagonist. [ABSTRACT FROM AUTHOR]

A novel radical phosphinylation of α,α-diaryl allylic alcohols with arylphosphine oxides was described for the direct preparation of α-aryl-β-phosphinylated carbonyl ketones in medium to good yields via 1,2-aryl migration. In this reaction, formation of new C(Ar)-C(sp³) and C(sp³)-P bonds was observed. [ABSTRACT FROM AUTHOR]

An efficient method for the construction of 6-alkyl phenanthridines by tert-butyl peroxybenzoate (TBPB)-mediated 2-isocyanobiaryl insertion with 1,4-dioxane was established. Two new C -C bonds were formed in this reaction via a sequential C(sp³)-H/C(sp²)-H bond functionalization under metal-free conditions. [ABSTRACT FROM AUTHOR]

A novel palladium-catalyzed three-component reaction for the synthesis of quinazolin-4(3H)-ones from readily available 2-aminobenzamides and aryl halides via a palladium-catalyzed isocyanide insertion/cyclization sequence has been developed. This methodology efficiently constructs quinazolin-4(3H)-ones in moderate to excellent yields with the advantages of operational simplicity. [ABSTRACT FROM AUTHOR]

I2-promoted domino reactions of isatins or 3-hydroxyindolin-2-one derivatives with enaminones under O2 conditions have been established. The reactions of isatins with enaminones afforded functionalized tetracyclic pyrrolo[2,3,4-kl]acridine derivatives in moderate to good yields through domino cyclization and C-H oxidation. The reactions of 3-hydroxyindolin-2-one derivatives with enaminones proceeded well to give functionalized pyrrolo[2,3,4-kl]acridine derivatives via tandem ring-opening/recyclization/methyl migration sequences with two C-C bonds cleaved. [ABSTRACT FROM AUTHOR]

A simple and efficient palladium-catalyzed carbonylative Sonogashira coupling via tert-butyl isocyanide insertion has been developed, which demonstrates the utility of isocyanides in intermolecular C-C bond construction. This methodology provides a novel pathway for the synthesis of alkynyl imines which can undergo simple silica gel catalyzed hydrolysis to afford alkynones. The approach is tolerant of a wide range of substrates and applicable to library synthesis. [ABSTRACT FROM AUTHOR]

A novel and highly efficient strategy for the synthesis of isocoumarins and phthalides through a palladium(O)-catalyzed reaction incorporating fert-butyl isocyanide has been developed. This process, providing one of the simplest methods for the synthesis of this class of valuable lactones, involves two steps including cydization reaction and simple acid hydrolysis. The methodology is tolerant of a wide range of substrates and applicable to library synthesis. [ABSTRACT FROM AUTHOR]

In acetic acid, Friedel-Crafts alkylation of indoles by tert-enamides proceeded effectively in the absence of any catalyst to afford the pharmacologically and biologically active 2-oxo-1-pyrrolidine derivatives in moderate to good yields. The mechanistic study based on the NMR and HRMS analysis shows that the reaction was promoted by acid catalysis. The hydrogen-bond interaction between tert-enamides and AcOH may also be responsible for the reaction. [ABSTRACT FROM AUTHOR]

In acetic acid, Friedel-Crafts alkylation of indoles by ferf-enamides proceeded effectively in the absence of any catalyst to afford the pharmacologically and biologically active 2-oxo-1-pyrrolidine derivatives in moderate to good yields. The mechanistic study based on the NMR and HRMS analysis shows that the reac-tion was promoted by acid catalysis. The hydrogen-bond interaction between ferf-enamides and AcOH may also be responsible for the reaction. [ABSTRACT FROM AUTHOR]

Utilizing 3,5-bis(x-pyridyl)-1,2,4-triazole(x-Hpytz, x = 3; x = 4) as multidentate ligands, six novel coordination polymers with Zn(ii) or Cd(ii) metal ions were prepared: [Zn(3-pytz)0.5(OH)0.5Cl]n(1, 1D ladder), {[Zn(3-Hpytz)(H2O)4] [Zn(3-Hpytz)(H2O)3·SO4]SO4·5H2O}n(2·5H2O, 1D chain), [Cd(3-Hpytz)(SO4)]n(3, 3D framework), {[Cd(3-Hyptz)SO4·3H2O]·2H2O}n(4·2H2O, 1D chain), [Zn(4-pytz)Cl]n(5, 3D framework) and [Zn2(4-pytz)(SO4)(OH)]n(6, 3D framework). All compounds were obtained from hydrothermal reactions, with the exception of compound 4which was obtained by solvent diffusion at room temperature. All compounds were characterized by FTIR, elemental analysis and TGA analysis and their structures were determined by X-ray diffraction. All compounds exhibited substantial thermal stability and showed photofluorescent properties that resulted from ligand π–π* transition. [ABSTRACT FROM AUTHOR]

A practical and efficient method for the synthesis of optically active O-acetyl cyanohydrins via one-pot lipase-catalyzed kinetic resolution of the in situ generated racemic cyanohydrins or O-acetyl cyanohydrins using an ionic liquid as both reaction media and promoter has been described. [ABSTRACT FROM AUTHOR]

A facile and efficient copper-catalyzed method for the synthesis of 4H-3,1-benzoxazin-4-one derivatives has been developed. This procedure is based on a tandem intramolecular C-N coupling/rearrangement process. This method would provide a new and useful strategy for construction of N-heterocycles. [ABSTRACT FROM AUTHOR]

α-functionalization of ferrocenyl alcohols by direct C-O bond activation by indoles, active methylene compounds, electron-rich arenes, anilines, alcohols, and thiols in acetic acid is described. This protocol provides a relatively green and efficient combinatorial access to ferrocene derivatives in a metal-free manner. [ABSTRACT FROM AUTHOR]