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Research has been conducted on polymeric complexes with rectangular channels. The study of these complexes constructed from Cu(II) ion, auxiliary ligands and 1,2,4,5-benzenetetracarboxylic acid is presented.

Research has been conducted on the three-dimensional channel-like lanthanide complexes. The synthesis and characterization of these complexes which have been constructed via the use of various compounds including 1,2,4,5-benzenetetracarboxylic acid have been carried out and the details are reported.

By using Pd(TFA)2/PCy3 as a catalyst, a broad range of aromatic carboxylic acids, including heteroaromatic carboxylic acids, efficiently underwent decarboxylative coupling with an array of polyfluoroarenes in the presence of stoichiometric amount of silver salts to generate biaryls. Silver salts were adjusted to the reactivity of aromatic carboxylic acids to efficiently suppress the protodecarboxylation and therefore improve decarboxylative cross-couplings. It was established that the palladium complex containing the PCy3 ligand was capable of catalyzing the decarboxylation of electron-rich aromatic carboxylic acids, and silver salts promoted the decarboxylation of both electron-rich and -deficient ones. To explain the two different decarboxylation processes, two possible reaction pathways are proposed, which were further supported by the facts that the stoichiometric arylpalladium complex can directly arylate pentafluorobenzene in the presence of PCy3 and the arylpalladium complex can catalyze the decarboxylative coupling of 2,4-dimethoxybenzoic acid with pentafluorobenzene. The kinetic isotope effect of 4.0 clearly showed that the C-H bond cleavage of polyfluoroarenes is involved in the rate-determining step. [ABSTRACT FROM AUTHOR]

Pd-catalyzed decarboxylative Heck coupling of aromatic carboxylic acids with various olefins is developed using O2as the terminal oxidant. Enhancement of O2pressure leads to improving reaction turnover in this transformation and allows significantly reducing catalyst loading for efficient conversion of electron-rich benzoic acids. A Pd catalyst supported by a carbene ligand enables using electron-deficient benzoic acids as coupling partners. [ABSTRACT FROM AUTHOR]

A versatile palladium catalyst system was developed to effect the decarboxylative Heck coupling of a variety of arenecarboxylic acids with a wide range of olefins. The key to obtaining the efficient catalyst system is the use of 1-adamatanecarboxylic acid as additive. Alkyl-substituted olefins with coordinating groups were observed to provide significantly improved regioselectivity compared with other alkyl-substituted olefins lacking coordinating groups, and the acetate group of allylic ester was also tolerated in this reaction. [ABSTRACT FROM AUTHOR]

A porous polyhedral metal-organic framework has been constructed by utilizing Zn2(COO)4and Zn2(COO)3SBUs as nodes and the flexible hexacarboxylate as linkers. The framework contains four types of interconnected polyhedral cages, rhombic dodecahedron, tetrahedron, octahedron, and distorted tetragonal prism. To identify the topology of the whole network, the four types of polyhedral cages can be viewed as nodes, and the whole network is signed as a (6,6,12,12) network. In another view of point, the Zn2(COO)3SBU, Zn2(COO)4SBU and hexacarboxylate ligands can also be considered as nodes, then the network is simply signed as a (3,4,6)-connected net with a Schläfli symbol (43) (4462) (4679). [ABSTRACT FROM AUTHOR]