16819-43-5Relevant academic research and scientific papers
Single-crystal to single-crystal mechanical contraction of metal-organic frameworks through stereoselective postsynthetic bromination
Marshall, Ross J.,Griffin, Sarah L.,Wilson, Claire,Forgan, Ross S.
, p. 9527 - 9530 (2015)
The properties of metal-organic frameworks (MOFs) can be tuned by postsynthetic modification (PSM) to introduce specific functionalities after their synthesis. Typically, PSM is carried out on pendant functional groups or through metal/ligand exchange, preserving the structure of the MOF. We report herein the bromination of integral alkyne units in a pair of Zr4+ and Hf4+ MOFs, which proceeds stereoselectively in a single-crystal to single-crystal manner. The chemical and mechanical changes in the MOFs are extensively characterized, including the crystal structures of the postsynthetically brominated materials, which show a mechanical contraction of up to 3.7% in volume. The combination of stability and chemical reactivity in these MOFs leads to the possibility of tuning mechanical properties by chemical transformation while also opening up new routes to internal pore functionalization.
Synthesis, optical properties, crystal structures and phase behaviour of symmetric, conjugated ethynylarene-based rigid rods with terminal carboxylate groups
Fasina, Tolulope M.,Collings, Jonathan C.,Burke, Jacqueline M.,Batsanov, Andrei S.,Ward, Richard M.,Albesa-Jove, David,Porres, Laurent,Beeby, Andrew,Howard, Judith A. K.,Scott, Andrew J.,Clegg, William,Watt, Stephen W.,Viney, Christopher,Marder, Todd B.
, p. 690 - 697 (2005)
Sonogashira cross-coupling reactions of 4-ethynylmethylbenzoate (1) with aryl halides gave 1,2-bis(4-carbomethoxyphenyl)ethyne (2), 1,4-bis(4- carbomethoxyphenylethynyl)benzene (3), 1,4-bis(4-carbomethoxyphenylethynyl) tetrafluorobenzene (4) and 9,10-bis(4-carbomethoxyphenylethynyl)anthracene (5), protected precursors to conjugated rigid rod bis(carboxylato) ligands. The compound 1,4-bis(4-carbomethoxyphenyl)butadiyne (6) was prepared by the oxidative homo-coupling of 1. The hydrolysis of 2 and 3 by NaOH in methanol gave the sodium salts of the respective carboxylate anions and subsequent treatment with HCl gave the corresponding free carboxylic acids. Compounds 2-6 were characterised by absorption, emission, IR, NMR and mass spectrometry and examined for liquid crystal phase behaviour by differential thermal analysis (DTA) and transmitted polarised light microscopy (TPLM). Compound 4 exhibited a nematic phase stable from 233.6 °C until decomposition at 320 °C. The single-crystal structures of 2, 5 and 6 were determined by X-ray diffraction at 110-160 K. The Royal Society of Chemistry 2005.
A series of coordination networks constructed from the rigid ligand 4,4′-ethynylenedibenzoate: Topological diversity, entanglement, supramolecular interactions and photophysical properties
Martins,Resende,Ronconi
, p. 3103 - 3116 (2017)
Four coordination networks (CNs), i.e., [Co(edb)(H2O)(Py)2], 3; [Cd(edb)(DMSO)2]·0.5(DMSO), 4; [Er2(edb)3(DMSO)2(H2O)2], 5; and [Gd2(edb)3(H2O)4], 6 (edb2- = 4,4′-ethynylenedibenzoate), were synthesized and structurally characterized, and the luminescence properties of CNs 4 and 5 were investigated. In CN 3, the ligand adopts a bridging coordination mode that connects one Co(ii) ion to another, resulting in a 1D CN. CNs 4 and 5 contain binuclear centers that are linked to four ligands in the chelating and bridging coordination modes. CN 4 has a 2D → 3D inclined polycatenated structure, whereas CN 5 exhibits a 3D network because the voids created by the long ligand are stabilized by the π-π stacking interactions, thereby avoiding the entanglement of the structure. CN 6 has a paddle-wheel structure with a two-fold interpenetrated rob topology. The photophysical properties of the compound H2edb and CNs 4 and 5 were studied in the solid state. Compound 2 (H2edb) displays strong absorption bands at 325 and 350 nm and emission at 385 nm. Upon complexation with Er(III), the emission was quenched. The emissions of CN 4 were due to the intraligand transitions.
Synthesis of functionalized 1,2-diphenylacetylene derivatives
Lozanova,Stepanov,Mel′nik,Zlokazov,Veselovsky
, p. 64 - 67 (2019/04/25)
A series of new functionalized 1,2-diphenylacetylene derivatives, including those containing l-prolinamide substituents at the aromatic nuclei, was synthesized using the Sonogashira coupling at the key step.
Ligand-elaboration as a strategy for engendering structural diversity in porous metal-organic framework compounds
Gadzikwa, Tendai,Zeng, Bi-Shun,Hupp, Joseph T.,Nguyen, SonBinh T.
supporting information; experimental part, p. 3672 - 3674 (2009/02/05)
A series of 4,4′-ethynylenedibenzoic acids were synthesized and used in the construction of Zn-based, mixed-ligand metal-organic frameworks; through variation of functionality in the 3- and 3′-positions of these linkers, a collection of MOFs with differing connectivities and varying levels of interpenetration was obtained. The Royal Society of Chemistry.
Synthesis and investigation of phosphine ligands containing cationic guanidino functions in aqueous Heck reactions
Dibowski, Harald,Schmidtchen, Franz P.
, p. 2325 - 2330 (2007/10/02)
Phosphines 2 and 3 supplemented with strongly basic and hydrophilic guanidium functions were prepared for the first time. In combination with palladium acetate these ligands form active catalysts that promote an aqueous Heck reaction.
