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The azomethine ylides are generally used in 1,3-dipolar cycloadditions with various dipolarophiles. In this work, a new and diverse route has been developed for the azomethine ylides, for synthesis of novel pyrrole derivatives. The azomethine ylide, produced via C–H activation of unreactive C(sp3)–H bond of 2-methylquinoline, by molecular iodine, in the presence of pyridine. Herein, we represent novel pyrrole derivatives, synthesized from the reaction of pyridinium ylide with olefins, which formed via a reaction of isatin, dialkyl acetylenedicarboxylate derivatives and pyridine as a base in moderate to excellent yields. Various features of this cyclization, discussed.

This work reports the ambient temperature synthesis and structural characterisation of six new first row transition metal acetylenedicarboxylate coordination polymers. The Co and two Ni compounds adopt structures in which the octahedral metals are connected into 1D chains via the acetylenedicarboxylate ligand. In contrast the Mn and two Zn compounds adopt 3D metal-organic frameworks; while the Mn compound is non-porous the two Zn structures contain dimeric or trimeric clusters connected into frameworks that are potentially porous. These two anionic metal-organic frameworks are, however, charged balanced by cations siting in their pores which greatly reduces the ability to access their porosity.

Aims & Objective:In this work, pyran derivatives were synthesized via a multicomponent reaction of ninhydrin, α-haloketones, dialkyl acetylenedicarboxylate, and triphenylphosphine in the presence of iron oxide magnetic nanoparticles (Fe3O4-MNPs) as efficient nanocatalyst in ethanol at room temperature.Materials & Methods:The biosynthesis of Fe3O4-MNPs was performed by Clover Leaf water extract. In addition, antioxidant activity was examined for the prepared compounds employing DPPH radical scavenging and ferric reduction activity potential (FRAP) experiment and comparing results with synthetic antioxidants (TBHQ and BHT).Results:Compound 5b showed excellent radical trapping activity and good reducing activity relative to standards (BHT and TBHQ).Conclusion:Some advantages of this procedure are: the workup of reaction is easy and the products can be separated easily by filtration. Fe3O4-MNPs display a good improvement in the yield of the product and showed significant reusable activity.

In this work, stepwise reaction mechanism of the [2+3] cycloaddition reaction among alkyl isocyanides (contains tert-butyl isocyanide, cyclo hexyl isocyanide) with dialkyl acetylenedicarboxylate (contains dimethyl acetylenedicarboxylate, diethyl acetylenedicarboxylate and di-tert-butyl acetylenedicarboxylate) at the presence of acetic anhydride was investigated both in the gas phase and in solvent was studied theoretically. The potential energy of all structures participated in the reaction path was evaluated. The geometry of all the structures participated during the reaction path, the rate-determining step, and potential competitive routes during the reaction coordinate were evaluated. Also, dielectric constant effect of the solvent, the effect of substituted alkyl groups on the potential energy surfaces, and the best product configuration were investigated based upon the quantum mechanical calculations. For better understanding of the molecular interaction, the natural bond orbital method (NBO) and AIM analysis were applied. The results indicated that, the first step of the reaction was recognized as rate-determining step and the reaction rate was predicted to be dependent on the concentration of alkyl isocyanides and dialkyl acetylenedicarboxylate. It was also found that, the electron donating of different alkyl groups was not the main factor for the variation in the potential energy surfaces of the reaction; however, the steric factor of the bulky alkyl groups participating in the reaction path was found to be the main factor.

Anhydrous EuII–acetylenedicarboxylate (EuADC; ADC2− = −O2C‐C≡C‐CO2 −) was synthesized by reaction of EuBr2 with K2ADC or H2ADC in degassed water under oxygen‐free conditions. EuADC crystallizes in the SrADC type structure (I41/amd, Z=4) forming a 3D coordination polymer with a diamond‐like arrangement of Eu2+ nodes (msw topology including the connecting ADC2− linkers). Deep orange coloured EuADC is stable in air and starts decomposing upon heating in an argon atmosphere only at 440 °C. Measurements of the magnetic susceptibilities (μ eff=7.76 μB) and 151Eu Mössbauer spectra (δ=−13.25 mm s−1 at 78 K) confirm the existence of Eu2+ cations. Diffuse reflectance spectra indicate a direct optical band gap of E g=2.64 eV (470 nm), which is in accordance with the orange colour of the material. Surprisingly, EuADC does not show any photoluminescence under irradiation with UV light of different wavelengths. Similar to SrADC, EuADC exhibits a negative thermal volume expansion below room temperature with a volume expansion coefficient α V=−9.4(12)×10−6 K−1., Multifaceted! Orange coloured Eu(C4O4), the anhydrous EuII salt of acetylenedicarboxylic acid, has many interesting properties: it is stable in air for months, and upon heating in an inert atmosphere decomposition only starts at 440 °C. Below room temperature it shows a negative thermal volume expansion (NTE) and although containing EuII it does not exhibit any luminescence even at 10 K.

A facile and efficient one-pot three-component reaction method for the synthesis of thiazine-dicarboxylates is reported. Reaction of an isocyanide and dialkyl acetylenedicarboxylate with 2-amino-4H-1,3-thiazin-4-one derivatives containing both an acidic proton and an internal nucleophile gave the products in good yields of 76–85%. The reactivity of dialkyl acetylenedicarboxylates was further tested in the synthesis of thiazole-pyrimidines where a two-component reaction of 2-aminothiazole with dialkyl acetylenedicarboxylates was successfully converted to a more efficient three-component reaction of a thiourea, α-haloketone and dialkyl acetylenedicarboxylate (DMAD/DEtAD) to give thiazole-pyrimidines in good yields of 70–91%.

Nucleophilic addition of thiolates to diethyl acetylenedicarboxylate in chloroform at room temperature affords solely the meso dithioaddition product, whereas the addition of amines in ethanol gives only the corresponding (Z)-enamine, as confirmed by X-ray crystal analysis. The monoaddition product of thiolate addition, prepared and isolated at lower temperatures, also exhibited (Z)-stereochemistry. The accompanying computational study on simplified model systems explains the reasons for the observed stereochemistry and for acetylenedicarboxylate readily undergoing two addition reactions with thiolate nucleophiles and the (Z)-enamine being much less reactive toward addition of thiolate or amine nucleophiles.

An easy and rapid method for the synthesis of 3,4,5-substituted furan-2 (5H)-ones has been achieved through a three-component reaction of aniline, dialkyl acetylenedicarboxylate, and aromatic aldehydes using nanosilica-tethered polyhedral oligomeric silsesquioxanes with eight branches of 3-aminopropyltriethoxysilane as catalyst under ultrasonic irradiations. We reported a class of organic–inorganic hybrid material based on nanosilica-tethered polyhedral oligomeric silsesquioxanes with eight branches of 3-aminopropyltriethoxysilane (nanosilica @APTPOSS). The catalyst has been characterized by proton nuclear magnetic resonance (1H NMR), scanning electronic microscopy, energy dispersive X-ray, DLS (dynamic light scattering), and thermal gravimetric analysis. The high efficiency, short reaction times, simple workup, reusability of the catalyst up to six runs without considerable loss of activity, using the sonochemical procedure as green process, and an alternative energy source are some benefits of this method.

A one-pot approach for the synthesis of epoxypyrrolo[3,4-g]indazoles is presented. The first step was initiated by a three-component reaction of an isocyanide, a dialkyl acetylenedicarboxylate, and 2-furancarboxylic acid, and led to 1,3-dioxoepoxyisoindole, followed by the addition of hydrazonoyl chloride through a [3+2]-cycloaddition reaction in the second step. The key step in the formation of final compound involves a bicyclization strategy through intramolecular Diels–Alder­ (IMDA) reaction.

A convenient, expedient and efficient method for the synthesis of poly substituted dihydro-2-oxypyrroles is described via the one-pot four-condensation of dialkyl acetylenedicarboxylate, formaldehyde, and amines (aromatic and aliphatic) at ambient temperature in the presence of Manganese (II) Nitrate Tetrahydrate (Mn(NO 3 ) 2 .4H 2 O) as a cost effective and inexpensive catalyst. The present methodology provides a simple and eco-safe procedure for the synthesis of poly substituted dihydro-2-oxypyrroles with some additional advantages, such as good to high yields , short reaction times, avoidance of hazardous or toxic catalysts , simplicity of operating and work-up procedures with no necessity for chromatographic purification steps. Normal 0 false false false EN-US X-NONE AR-SA

8-Isoquinolinones derived from a silver-catalyzed cycloisomerization of in situ formed ortho-alkynylsalicylaldimines react with 1 equiv of acetylenedicarboxylate derivatives to give pyrano[2,3,4- ij]isoquinolines through a [4 + 2]-cycloaddition reaction. When 2 equiv of the alkyne are used, structurally complex benzo[ de]chromenes are obtained through an intricate cascade process comprising unusual formal [4 + 2]- and [2 + 2]-cycloadditions followed by several ring-opening and ring-closing processes.

The most contracted cerium(IV)-based metal–organic framework (MOF) with fcu topology incorporating an alkyne-based linker, namely acetylenedicarboxylate (ADC), was synthesized under green conditions in water at room temperature and thoroughly characterized. The structure of this new MOF, denoted as Ce-HHU-1, was determined from powder X-ray diffraction data and Rietveld refinement and is made up of octahedral [Ce6O4(OH)4]12+ clusters, each of which is connected to other inorganic units by twelve ADC linkers to give a porous network with fcu topology analogous with UiO-66. The permanent microporosity of Ce-HHU-1 was confirmed by nitrogen sorption, meanwhile its high hydrophilicity was displayed by a type I water vapor sorption isotherm. The adsorption of CO2 in Ce-HHU-1 features a remarkably high zero-coverage isosteric heat of adsorption of 47 kJ mol−1, attributed to the presence of the –CC– triple-bond in the framework. The latter also allows for Ce-HHU-1 to capture and irreversibly chemisorb Br2 vapors, as well as both chemi- and physisorb I2 vapors in an effective manner, making this material potentially applicable for air cleaning from toxic halogen vapors.

A three-component reaction of antiaromatic meso-mesityl-3-nitronorcorrolatonickel(II) 1-NO2 with dialkyl acetylenedicarboxylate and PBu3 yields aromatic zwitterionic corrole nickel(II) complexes 3-R with one of the meso-substituents comprising a positively charged tributyl phosphonium group and negatively charged coordination core. Reaction of 1-NO2 with PBu3 alone resulted in a nonaromatic chiral adduct 5 of a zwitterionic phlorine character with a −PBu3+ group at a pyrrole β-position.

In this research, the mechanism of the reaction between triphenylphosphine R1 and dialkyl acetylenedicarboxylate R2 was investigated in the presence of NH-acid, such as benzotriazole R3 based on the quantum mechanical calculations. Theoretical studies performed for evaluation of the potential energy surfaces of all structures participated in the reaction mechanism. All structures were optimized at the B3LYP/6-311+ + g(d,p) levels. The first step of the reaction was recognized as a rate-determining step in the reaction mechanism. To check the effect of solvent on the potential energy surfaces, condensed phase calculations in dichloroethane were carried out with the polarizable continuum model. To check the effect of the structure of reactant on the potential energy surfaces, the reaction mechanism was examined in the presence of dimethyl acetylenedicarboxylate R2-M and di-tert-butylacetylenedicarboxylate R2-T. Finally, the natural bond orbital method was applied for a better understanding of molecular interaction.

Big spherulite structure and high crystallinity are the two main drawbacks of poly(butylene succinate) (PBS) and hinder its application. In this work, a new type of copolyester poly(butylene succinate-co-butylene acetylenedicarboxylate) (PBSAD) is synthesized. With the incorporation of acetylenedicarboxylate (AD) units into PBS chains, the crystallization temperature and crystallinity are depressed by excluding AD units to the amorphous region. In contrast, the primary nucleation capability is significantly strengthened, without changing the crystal modification or crystallization kinetics, leading to the recovery of total crystallization rate of PBSAD under the same supercooling condition. The existence of specific interaction among AD units is found to be crucial. Although it is too weak to contribute to the melt memory effect at elevated temperature, the interaction continuously strengthens as the temperature falls down, and the heterogeneous aggregation of AD units keeps growing. When the aggregating process reaches a certain extent, it will induce the formation of a significant amount of crystal nuclei. The unveiled nucleation mechanism helps to design PBS copolymer with good performance.

In this paper, we aimed at synthesizing GO/H2L-Pd nano-composites (graphene-oxide/schiff base N2O4 Ligand-palladium) as a new heterogeneous catalyst. Different analytical techniques were applied in order to analyze the chemical composition and the structure of the catalyst. The findings revealed that GO/H2L-Pd could catalyze synthesis of furan derivatives in one-pot three-component condensation reaction by different aromatic aldehydes, arylamine and acetylenedicarboxylate. The major advantages of this study are the green and mild procedure, easy reaction work-up, short reaction time, high yields, and reusability of the catalyst.

The reaction of cyclohexane-annulated 3 a,6a-diaza-1,4-diphosphapentalene (DDP) with di-tert-butyl acetylenedicarboxylate (DBAD) affords the 1,3-dipolar cycloaddition product of the acetylene moiety to the phosphorus and sp2-carbon atoms of DDP in 90% yield. No individual products were isolated in the reaction of DDP with dimethyl acetylenedicarboxylate (DMAD). In the three-component DDP–DMAD–carbazole system (1: 2: 1), a product was generated in 73% yield via successive reactions, including the 1(P),3(C)-dipolar cycloaddition of DMAD to DDP, the addition of the second equivalent of DMAD to the three-coordinate phosphorus atom of the intermediate, and the NH addition of carbazole at the unsaturated C=C bond of the second DMAD moiety. The structures of the reaction products were established by X-ray diffraction.

Three-component reactions of oxindole derivatives, thiosemicarbazide with dialkyl acetylenedicarboxylate (or maleimide) led to novel indole-hydrazono thiazolidinones in high-to-excellent yields. The antioxidant activities of the synthesized compounds were studied by 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. Among the products, those with amide moiety exhibited better antioxidant activities than other ester derivatives of indole-hydrazono thiazolidinones. Minimum bactericidal concentration (MBC) was evaluated against Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) at different concentrations. However, the MBC values for compounds with amide group in their skeleton exhibited higher antibacterial activity than compounds with ester group. Therefore, it is assumed that these compounds could be used as effective antioxidant and antibacterial agents.

Two hitherto unknown one-dimensional coordination polymers (1D CPs) [M(adc)(4-spy)2(H2O)2]n, (M = Mn(II) (1) and Co(II) (2); H2adc = acetylenedicarboxylic acid and 4-spy = 4-styrylpyridine) have been characterized by infrared spectra, elemental analysis, thermogravimetric analyses (TGA), powder X-ray diffraction (PXRD) patterns and single-crystal X-ray diffraction techniques. Both these compounds 1 and 2, are isostructural and construct 3D supramolecular networks by the combination of hydrogen bonding and C–H···π interactions. Interestingly, these two materials exhibit variable temperature magnetic moment. Two new isostructural coordination polymers have been synthesized using linear spacer ligand acetylenedicarboxylate and monodented 4-styrylpyridine ligands. The X-ray crystallographic analysis exhibits that both the compounds form 1D chain structures which undergo hydrogen bonding and C–H···π interactions to furnish 3D supramolecular architectures. Effect of metal ion on variable temperature magnetic moment has been studied.

A strategy was developed to obtain from acetylenedicarboxylic acid either an acetylenedicarboxylate-based ZrIV metal-organic framework (MOF) with fcu topology or a halo-functionalized-MOF-801 through in situ ligand hydrohalogenation. The new materials feature exceptionally high hydrophilicity and CO2 /H2 adsorption energetics. The acetylenedicarboxylate linker and its functionalizable triple-bond discloses its potential in the engineering of microporous materials with targeted properties.

A new convenient strategy for the synthesis of 3-hydroxy-2-pyrrolidinone derivatives featuring regioselective C C coupling has been developed. This is a Cu (II) catalyzed cross dehydrogenative coupling (CDC) involving enamino-ketones of benzyl amines and di-alkyl acetylenedicarboxylate, followed by cyclization by primary amines. TBHP (tert-butyl hydroperoxide) has been used as the oxidant to promote the coupling protocol. This synthetic route principally demonstrates the scope of CDC reaction and also applicable to gram-scale synthesis.

New chromene derivatives, 9H-furo[2,3-f]chromene-7,8-dicarboxylates, have been synthesized in high yields by a three-component reaction of euparin (isolated from Petasites hybridus), an aldehyde, and dialkyl acetylenedicarboxylate in the presence of PPh3 and catalytic amount of ZnO nanorods under solvent-free conditions at room temperature. ZnO nanorods showed a strong effect on improving the yield of the desired products. Chromene derivatives can be easily separated from the reaction mixture in a simple work-up, and the catalyst may be recovered and reused without considerable loss of activity.

An efficient and catalyst-free for the synthesis of dialkyl 5-(aryl)-4-(1,3-dicarbonyl)-1-(aryl)-1H-pyrrole-2,3-dicarboxylate via a novel one-pot four-component reaction of arylamine, acetylenedicarboxylate, arylglyoxal, and 1,3-dicarbonyl compounds in ethanol is reported. All the products were obtained in excellent yields and their structures were established from their spectroscopic data.

A regioselective and convenient method for the synthesis of fully substituted pyrazole derivatives was developed from the 1,3-dipolar cycloaddition reaction of nitrile imine generated in situ from hydrazonoyl chloride and Et3N with 1,4-benzothiazin-3(4H)-one. The structure of the target molecule 3d was confirmed by X-ray diffraction. An efficient synthesis of a series of 1H-pyrazole-4-carboxylate is reported. A multicomponent reaction was designed using 2-aminothiophenol, dialkyl acetylenedicarboxylate, and hydrazonoyl chloride in the presence of Et3N in EtOH at room temperature. The structure of the target molecules was confirmed by X-ray diffraction.

In this study, an acetylenedicarboxylate based binuclear Cu(II) compound [Cu2(adc)(4-pic)6(H2O)4][ClO4]2 (1) (H2adc = acetylenedicarboxylic acid and 4-pic = 4-picolene) has been synthesized and well characterized using elemental analysis, infrared (IR) spectra, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) patterns and single crystal X-ray diffraction (SCXRD) techniques. The binuclear compound undergoes hydrogen bonding interactions to form a 1D hydrogen bonded aggregate, which further undergoes extensive edge-to-face C–H⋯π interactions to form a 3D supramolecular motif. The current conductivity of compound 1 was recorded under dark and illuminated conditions. Interestingly, the measured I–V characteristics of the synthesized material in the dark and under the illumination of incident light exhibit a highly non-linear rectifying behavior signifying a Schottky diode nature. Furthermore, the enhancement of values of the electrical parameters after exposure to illumination of incident radiation indicates the light sensing behaviour of the material. Therefore, the material can be used as a promising candidate in photosensitive electronic devices.

The reaction between acetylenedicarboxylic acid and nicotinamide or isonicotinamide produces two new zwitterionic molecules, namely (Z)-2-(3-carbamoylpyridin-1-ium-1-yl)-3-carboxyacrylate (1) and (Z)-2-(4-carbamoylpyridin-1-ium-1-yl)-3-carboxyacrylate (2), as well as a salt by-product, 4-carbamoylpyridinium acetylenedicarboxylate (2a). The solid-state behaviour of the zwitterions has been investigated by altering variables such as the solvent(s) used for synthesis and crystallisation, and the temperature at which these occur. Zwitterions 1 and 2, as well as a previously reported zwitterion, (Z)-2-(4-cyanopyridin-1-ium-1-yl)-3-carboxyacrylate (3), were combined with various small organic co-formers in an attempt to form multi-component crystals via both mechanochemical and solution methods. Three new hydrated salts were formed with melamine (1·melamine, 2·melamine, and 3·melamine), all of which display extensive charge-assisted hydrogen-bonding networks. Zwitterions 1 and 2 also form the characteristic R22(8) hydrogen-bond motif between the amide group and melaminium. Based on these observed trends in hydrogen bonding, further crystallisation experiments were attempted with molecules with similar hydrogen bonding capability to melamine. Although single crystals were not obtained, six potential salts have been identified based on PXRD, NMR and IR data. Compared to the number of co-formers used, the discovery of only three salts per zwitterion is unusual – a Cambridge Structural Database analysis indicates that this may be due to the robust nature of the hydrogen bonds between zwitterions themselves.

In this work, a novel, convenient, and efficient approach to the synthesis of pyrano[2,3-h]coumarins has been reported based on the multicomponent reaction. The one-pot reaction between 5,7-dihydroxy-4-methylcoumarin, dialkyl acetylenedicarboxylate and aromatic aldehydes catalyzed by sodium carbonate lead to the formation of a novel class of pyrano[2,3-h]coumarin derivatives. High atom-economy, excellent yields, simple procedure, and mild reaction conditions are the important features of this protocol. This method allows access to a variety of pyrano[2,3-h]coumarins via using a broad substrate scope.

The crystal structures of 3∞[RE2(ADC)3(H2O)6]·2H2O (RE = Pr, Nd, Sm, Eu, Tb, Dy) were solved and refined from X-ray single crystal data. They crystallize in a structure type already known for RE = La, Ce and Gd (P1, no. 2, Z = 2), which is characterized by REO9 polyhedra forming dimeric units being the nodes of a 3D framework structure linked by ADC2– anions (–O2C–C≡C–CO2– = acetylenedicarboxylate). From synchrotron powder diffraction data it was shown that isostructural coordination networks are formed for RE = Ho, Er, Y, whereas for RE = Tm, Yb, Lu a new structure type crystallizing in a highly complex crystal structure with a large orthorhombic unit cell is found. All compounds are obtained by slow evaporation of an aqueous solution containing RE(OAc)3·xH2O and acetylenedicarboxylic acid (H2ADC). The coordination networks of composition 3∞[RE2(ADC)3(H2O)6]·2H2O were thoroughly investigated by thermal analysis and for RE = Eu, Tb, a strong red and green photoluminescence was observed and investigated by means of UV/Vis spectroscopy.