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By employing a carboxylate ligand derived from benzene-1,4-dicarboxylate, a chemically stable Zn4O-based self-penetrating metal–organic framework has been rationally synthesized, which exhibits high CO2 adsorption and efficient catalytic conversion for CO2 cycloaddition. [ABSTRACT FROM AUTHOR]

Four new isostructural lanthanide–organic frameworks, [Ln(L)(H2O)2]·H2O·CH3CN (1-Ln) (Ln = Eu, Tb, Dy, and Gd), have been successfully synthesized via solvothermal reactions with a semi-rigid V-shaped multicarboxylate ligand 2-(2′,4′-dicarboxylphenoxy) benzoic acid (H3L) and Ln(NO3)3·6H2O. 1-Ln shows 2D layer-by-layer frameworks with interlayer channels decorated by carboxylate groups. 1-Eu exhibits excellent luminescence properties, and therefore, is chosen as a probe for sensing different metal ions and anions. Consequently, 1-Eu displays high selectivity and sensitivity for Fe3+ and Cr6+ ions, simultaneously, through the luminescence quenching effect, and thus, should be an excellent candidate for probing these pollutant metal ions. In addition, antiferromagnetic exchange interactions also exist between the Dy3+ ions in 1-Dy. [ABSTRACT FROM AUTHOR]

A novel and efficient copper-catalyzed radical cross-coupling of 1,3-dicarbonyl compounds with terminal alkenes for the synthesis of tetracarbonyl compounds with a quaternary carbon atom has been developed. Mechanistically, this transformation involves the construction of two C–C bonds and two C=O bonds in a one-pot process. The reaction tolerates a wide range of functional groups and proceeds under mild conditions. [ABSTRACT FROM AUTHOR]

A new 2D highly flexible and breathing porous framework [CuL(Me2NH)]·DMF·H2O (1) (H3L = 5-(4′-carboxylphenoxy)nicotinic acid) has been synthesized using a tritopic linker with a flexible joint. The desolvated framework, [CuL(Me2NH)] (1a), undergoes structural contraction, and exhibits selective and double-step hysteretic adsorption for CO2. Furthermore, on exposure to CH2Cl2 at room temperature, a unique single-crystal-to-single-crystal transformation occurred between 1 and [Cu2L2(Me2NH)2(H2O)2]·5H2O (1b). [ABSTRACT FROM AUTHOR]

Structural transformation has aroused wide interest and has emerged as a promising approach for the design and synthesis of novel coordination polymers. In this work, we found interesting structural transformation phenomena triggered from a nickel coordination polymer (CP). Two temperature-dependent two-dimensional (2D) CPs, 1 and 2 were synthesized from hydrothermal reactions, while the other two CPs, 2D 3 and 3D 4 were the products of the in situ thermal decomposition of 1. Interestingly, 1 could undergo methanol-mediated transformation to afford 2 and 2 might convert to 1 under the condition of adding bipy in water. The multi-step conversions from 1 to 3 and 3 to 4 triggered by heat treatment in the solid state accompany the very rare dynamic response of a sequential release of coordinated water and partial organic ligands. More importantly, the mechanism of the transformation has also been studied in detail. Moreover, 3 could revert back to 1 quickly upon exposure to air, and this reversible process of dehydration–rehydration could be repeated at least ten times, which could highlight the application for their use in moisture sensors. [ABSTRACT FROM AUTHOR]

An efficient copper-promoted oxidative coupling of enamides with alkynes has been developed for the synthesis of substituted pyrroles. The reaction proceeded through CH and NH bond functionalization of enamides under mild conditions. [ABSTRACT FROM AUTHOR]

Palladium and CO.: The title reaction proceeds in the presence of CO, thus providing a synthesis for 1,3‐oxazin‐6‐ones (see scheme; DABCO=1,4‐diazabicyclo[2.2.2]octane, DMF=N,N‐dimethylformamide). The reaction tolerates a variety of functional groups on both the aryl ring and the amide of the substrate. Initial mechanistic studies suggest the activation of the alkenyl CH bond to be a key step. [ABSTRACT FROM AUTHOR]

Two new zinc(II) metal-organic compounds, {[Zn(ADC)(bib)]·CH3OH·H2O}n(1) and [Zn(ADA)(bib)]n(2) (H2ADC = 1,3-adamantanedicarboxylic acid, H2ADA = 1,3-adamantanediacetic acid, bib = 1,4-bis(2-methyl-imidazol-1-yl)butane), have been synthesized and characterized. In1, zinc(II) ions are bridged by ADC to form a 1-D chain. The chains are further connected by bib to form a 2-D wave structure. In2, zinc(II) ions are bridged by two ADA to form a 1-D looped chain, and then the 1-D looped chain is connected through bib resulting in a 2-D network. Fluorescent properties, TG analysis, and XRPD for1and2are also measured and discussed. [ABSTRACT FROM PUBLISHER]

Three new 3D Mn(ii)-MOFs have been synthesized via solvothermal reaction with MnCl2·4H2O and [1,1′:4′,1′′-terphenyl]-2′,4,4′′,5′-tetracarboxylic acid (H4tptc) in three different solvents [N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMA) and N,N-dimethylformamide (DMF)], namely, [Mn2(tptc)(H2O)(NMP)]·NMP (1), [Mn2(tptc)(H2O)(DMA)]·DMA (2) and Mn2(tptc)(DMF)2 (3), all of which were fully characterized. In 1 and 2, the 1D uniform Mn–carboxylate chains with the (μ-EO-H2O/NMP/DMA)(μ-COO)2 triple bridges (EO = end-on) are extended by the tptc linkers to form a 3D (3,4)-connected fry net with 1D irregular quadrangular channels. Interestingly, 3 possess two kinds of Mn–carboxylate chains and can also be simplified as a fry net. The self-assembly synthesis system responds to small carbonyl solvents (NMP, DMA and DMF) with very high sensitivity and selectivity, but products using hydroxy solvents (methanol, alcohol and isopropanol) were not identified. The various pore frameworks of 1–3 are filled by different coordinated and latticed solvent molecules in their channels. The sizes of the channels [3 (33.11 Å2) ＜ 2 (35.17 Å2) ＜ 1 (35.37 Å2)] are induced by the sizes of the solvent molecules (DMF ＜ DMA ＜ NMP). The good chemical stabilities of 1–3 were observed. Magnetic studies demonstrate that the magnetic coupling through the mixed carboxylate bridges in all compounds is antiferromagnetic. [ABSTRACT FROM AUTHOR]

Two new metal–organic compounds, [Ag2(HADC)2(bimh)] (1) and [Cd(ADC)(bpp)]n(2) [H2ADC = 1,3-adamantanedicarboxylic acid, bimh = 1,6-bis(2-methyl-imidazole-1-yl)hexane, bpp = 1,3-bis(4-pyridyl)propane], have been synthesized and characterized. Compound1exhibits a discrete symmetric unit with 0D?2D interpenetrating structure. Compound2crystallizes in a chiral space groupP212121and presents a threefold interpenetrated 3D diamondoid network containing three helical chains. Thermal stability, X-ray powder diffraction, and luminescence for1and2are also measured and discussed. [ABSTRACT FROM PUBLISHER]

Two new coordination polymers, [Pb(bpdc)] n (1) and [Co(bpdc)(phen)] n (2) [H2bpdc = benzophenone-2,4′-dicarboxylic acid, phen = 1,10-phenanthroline], have been synthesized and structurally characterized. Hydrogen bonding and π ··· π stacking extend 1 and 2 into 3-D supramolecular architectures, where 1 exhibits a 3-D framework with 1-D hairpin-like helicates based on Pb–O covalent bonds and 2 displays a 3-D network with 1-D zipper-like chains based on Co–O and Co–N covalent bonds. The FT-IR spectra, PXRD and TG analyses are discussed for 1 and 2. Fluorescence spectra and luminescent lifetime are studied for 1. [ABSTRACT FROM PUBLISHER]

A noveland efficient palladium-catalyzed intramolecular oxidativecyclization of tertiary enamines for the synthesis of 1,3,4-trisubstitutedpyrroles and 1,3-disubstituted indoles has been developed. Trifluoroaceticacid plays an important role in the reaction. A series of pyrrolesand indoles with substitution patterns that are not easily accessibleby traditional routes were synthesized in good yields under mild conditions. [ABSTRACT FROM AUTHOR]

A noveland efficient palladium(II)-catalyzed alkenyl C–Hactivation oxidative annulation of enamides with alkynes for the synthesisof substituted pyrroles has been developed. The reaction toleratesa wide range of functional groups and is a reliable method for thesynthesis of triaryl-substituted pyrroles in high yields. [ABSTRACT FROM AUTHOR]

A novel Cu(TFA)2-catalyzed oxidative tandem cyclization/1,2-alkyl migration of readily available enamino amides for the synthesis of pyrrolin-4-ones has been developed. The reaction tolerates a wide range of functional groups and is a reliable method for the rapid synthesis of substituted pyrrolin-4-ones in high yields under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis, structure and magnetic property of a new coordination network {[Co2(bcp)2(bipy)]}n (1) (H2bcp=1,3-bis(4-carboxy-phenoxy)propane and bipy=4,4′-pyridine), are reported. Compound 1 shows two identical 2D layers with 22.48.65 topology which are interpenetrated in a parallel fashion, resulting in a twofold interpenetrating motif containing polyrotaxane and polycatenane characters. Magnetic susceptibility indicated the antiferromagnetic exchange interaction. The magnetic behavior of 1 can be explained by the tilts of local distortion axes. [Copyright &y& Elsevier]

A mild and efficient palladium-catalyzed cross-coupling between fluorinated vinyl chloride and arylboronic acids is described. The use of ligand B successfully overcomes the strong electronic withdrawing of trifluoromethylated substrates and allows the efficient synthesis of a wide range of α and α,β-trifluoromethyl containing olefins. By using this method, the key intermediate for synthesis of Efavirenz can be obtained in a simple route. The efficient conversion of two freon molecules into useful α and α,β-trifluoromethyl containing olefins is a useful route in organic chemistry. [ABSTRACT FROM AUTHOR]

Reaction conditions A) and B) are found to be highly efficient for the preparation of various title compounds including the high-affinity 5-HT3 receptor antagonist (XVI), which are not easily accessible by traditional procedures. [ABSTRACT FROM AUTHOR]

The method is only applicable to aryl-substituted enamides, whereas aliphatic ones do not react. [ABSTRACT FROM AUTHOR]

In contrast to monoalkylmonoarylketoxime carboxylates, dialkylketoxime carboxylates do not react under the employed conditions. [ABSTRACT FROM AUTHOR]

A facilebenzoyl peroxide (BPO) mediated ortho-hydroxylationand benzoylation of N-alkyl anilinesfor the synthesis of 2-benzamidophenols has been developed.The reaction tolerates a wide range of functional groups and is agood method for the straightforward synthesis of valuable 2-benzamidophenolsin good yields under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: A new three-dimensional porous framework [Co2(bpdc)2(H2bpz)]∙2(DMF)·5(H2O) (1) (H2bpdc=4,4′-biphenyldicarboxylic acid, H2bpz=3,3′,5,5′-tetramethyl-4,4′-bipyrazole) has been solvothermally synthesized by employing mixed H2bpdc and H2bpz ligands. 1 is a pillared-layer framework based on a binuclear paddle-wheel Co2(O2C-R)4 cluster, and exhibits a 2-fold interpenetrated 6-connected pcu topology. H2bpz bridges Co2(O2C-R)4 clusters with an angular coordination configuration to form interesting left- and right-handed helical chains. 1 possesses a two-dimensional porous system decorated by uncoordinated pyrazole –NH groups of H2bpz, leading to high adsorption selectivities for CO2 over N2 and H2. In addition, the strong antiferromagnetic interactions between the Co2+ ions in cluster were observed. [Copyright &y& Elsevier]

The utility of this method is demonstrated in the synthesis of zolimidine (IIIg). [ABSTRACT FROM AUTHOR]

A novel and efficient Cu-catalyzed intermolecular 5-endo-trig cyclization of ketoxime carboxylates for the synthesis of 2-arylpyrroles is developed. [ABSTRACT FROM AUTHOR]