
Abstract Book RHODIUM PORPHYRIN CATALYZED HYDRODEBROMINATION WITH WATER Yang, W, Chan, K.S. e-mail: [email protected] Department of Chemistry, Chinese University of Hong Kong, Shatin, N.T. Hong Kong, China In the course of exploring the carbon-carbon bond activation of cyclopropane, we have discovered 1,1,dibromo-2-phenylcyclopropane undergoes rhodium porphyrin catalyzed hydrogenation with water as the hydrogenating agent to give 2-bromo-1-phenylpropene with one C-Br undergoing hydrodebromination. We have extended this hydrodebromination with water to other allylic and benzylic bromides and will report the results. 1 Synthesis, characterization and DFT evaluation of trinuclear clusters containing isocyanides Shawkataly, O. B.1, Sirat, S. S.1 and Goh, C. P.1 [email protected] 1Chemical Sciences Programme, School of Distance Education, Universiti Sains Malaysia, Penang, Malaysia The chemistry of trinuclear carbonyl from Group 8 is dominated by the reactions of Group 15 ligands, particularly tertiary phosphines, phosphites or arsines. These ligands are widely studied in metal cluster chemistry due to their steric and electronic effects that are easily tunable. However, not many mono-, di and tri-substituted clusters containing isocyanide ligands have been structurally characterized. Thus, the structures of Ru3(CO)11[(CNC6H3(CH3)2], Os3(CO)11[(CNC6H3(CH3)2], Ru3(CO)10[(CNC6H3(CH3)2]2 and Os3(CO)9[(CNC6H3(CH3)2]3 had been synthesized and their molecular structures determined using single crystal X-ray crystallography method. Generally, isocyanide ligands coordinates at the axial position on metal cluster, while phosphines and arsine ligands tend to coordinate at equatorial position. However, in this work, it was found that the 2,6-dimethyl isocyanide ligand was coordinated to equatorial position on Ru3(CO)11[(CNC6H3(CH3)2] while in Os3(CO)11[(CNC6H3(CH3)2] it is at the axial position. Such deviation in ligand site preference is cannot be explained purely based on steric hindrance of the isocyanide ligand to the metal cluster. Thus, the geometry structures with the isocyanide ligand located at either equatorial/axial site were simulated. The theoretical studies were conducted in order to investigate whether or not the ligand site preference of these ligands correlates to the electronic effects. The electronic structure details obtained have provided supportive explanation on the deviation of the ligand site selection. Ru3(CO)11[(CNC6H3(CH3)2] Os3(CO)11[(CNC6H3(CH3)2] 2 11 CO2 adsorption in porous coordination frameworks Southon, Peter D1, Perkins, Gary2, Kepert, Cameron J1 and Pascali, Giancarlo2 [email protected] 1 School of Chemistry, The University of Sydney, Australia 2 Camperdown Cyclotron Facility, Australian Nuclear Science and Technology Organisation, Sydney, Australia In this work we report a novel application for CO2 capture materials. A range of porous coordination frameworks (or metal-organic frameworks), already known to selectively 11 adsorb CO2, have been used to capture CO2 generated by a cyclotron. This opens up a means to improve the efficiency of radiopharmaceutical synthesis, and also a potential method to characterise and map CO2 adsorption systems. Positron Emission Tomography is an important method for non-invasive monitoring of metabolic processes and molecular targets. Imaging agents incorporating 11C are used for cancer diagnosis and drug research, but the half-life of 20 minutes makes the rapid 11 11 separation and use of this isotope imperative. C is generated in a cyclotron as CO2 at ppm concentrations, and is usually separated using a liquid nitrogen trap. We report a series of experiments in which a set of coordination-framework materials are tested for 11 CO2 adsorption at low concentrations: UiO-66, amino-modified UiO-66, Mg(dobdc), ethylendiamine-appended Mg(dobdc), and Fe3[Co(CN)6]2 Prussian Blue, as well as reference materials Carbosphere and Zeolite 4A. Release profiles were measured as the materials were heated and substantial differences between materials were observed, which we relate to their sorption properties. We found that the UiO-66 based materials substantially outperformed the other candidates, with a comparatively high temperature for 11 100% capture and a narrow release profile. We have also shown that capture of CO2 by UiO-66 directly from the cyclotron is feasible. The implications both for improved radiopharmaceutical synthesis and novel methods for characterisation of CO2 capture systems will be discussed. 70 75 Activity in UiO-66 60 MOF Temperature 50 50 25 40 0 30 Activity / TBq / Activity -25 / C Temperature 20 10 -50 0 -75 0 5 10 15 20 3 Time / min II II 3D Hofmann Clathrate [M Pt (CN)4]∞ (M = Co, Ni) Synthesized by Postsynthetic Reductive Elimination Takaishi, S1, Okamura, T1, Iguchi, H1, Breedlove, B, K1, Kosaka, W2, Miyasaka, H2, Yamashita, M1,3 Presenting author’s e-mail: [email protected] 1 Graduate School of Science, Tohoku University, Sendai, Japan 2 Institute for Materials Research, Tohoku University, Sendai, Japan 3 Advanced Institute for Materials Research, Tohoku University, Sendai, Japan Metal-organic frameworks (MOFs) have been attracted much attention because they can be potentially used in a wide range of applications, such as gas storage, gas separation, chemical sensing, and chemical catalysis. Among them, cyano-bridged MOFs have been extensively studied because of their striking magnetic, photomagnetic, electrochemical, and adsorption properties. Especially, MOFs based on the square planar divalent II 2– tetracyanometalate [M (CN)4] (M = Ni, Pd and Pt) assemble with divalent transition metal ions (M' = Fe, Co, Ni, Cu, Zn and Cd), which are known as two dimensional Hofmann type clathrates ([M'M(CN)4]∞·nH2O.), have been interested in catalytic properties. Although some form 3D frameworks by connecting the 2D layer each other using pillar ligands such as pyrazine, there are no examples of 3D frameworks without using pillar ligands to the best of our knowledge. Furthermore, such a pillared layer structure has a drawback from the viewpoint of catalytic properties because the pillar ligands occupy the axial site of the M', which block the open metal sites. In this presentation, we report novel 3D MOFs II IV [M (H2O)2Pt (CN)4Br2]∞·8/3(H2O) (1: M = Co, 2: M = Ni) with an NbO topology using tetravalent dibromotetracyanoplatinate(IV) ion. Although these MOFs have no accessible pores for gas adsorption, we found that the axial and crystallization water molecules as well as axial Br ions on the Pt ions could be eliminated, accompanied by reduction of the Pt II II II II ions, by heating, affording porous frameworks [Co Pt (CN)4]∞ (1') and [Ni Pt (CN)4]∞ (2'). In this presentation, we report pore formation via post-synthetic reductive elimination and desolvation and the structures of the new MOFs as well as catalytic properties. 4 A BIOHYBRID CATALYST USING A HEME-POCKET WITH AN ARTIFICIAL METALLOCOMPLEX Hayashi, T, Onoda, A, Oohora, K [email protected] Osaka University, Suita, Japan Hemoproteins are well-known and versatile metalloproteins. These proteins have a heme cofactor located within the interior of the protein. One of the heme cofactors, protoheme IX (heme b), is non-covalently bound within the heme pocket. Thus, the heme b-containing hemoproteins can generally be converted into the apo-form under acidic conditions, and the addition of heme b or an appropriate metal complex into a solution of the apoprotein triggers refolding to generate the corresponding reconstituted protein. Our group has focused on this process and devoted our efforts to obtain a series of modified hemoproteins with artificially created cofactors, because it is found that a hemoprotein pocket after the removal of native heme is useful for an attractive scaffold as a metallocomplex-linked site to produce a new biocatalyst. In this presentation, several examples of reconstituted hemoproteins will be presented: (1) Replacement of heme b in myoglobin with manganese porphycene provides a catalytic activity toward the hydroxylation of several inert alkanes via C(sp3)–H bond activation (Oohora 2013). (2) Conjugation of a diiron-carbonyl cluster with apocytochrome c is found to give a new [FeFe]-hydrogenase model which generates H2 in the presence of a Ru complex as a photosensitizer (Onoda 2011). Furthermore, our group also prepares the second generation of the hydrogenase model using aponitrobindin consisting of a -barrel structure with the diiron-carbonyl cluster. (3) Insertion of an organorhodium complex into the cavity of aponitrobindin via covalent linkage provides a polymerization catalyst for phenylacetylene in an aqueous media (Onoda 2014). 5 A NEW FUNDAMENTAL TYPE OF CONFORMATIONAL ISOMERISM REVEALED Canfield, PJ1,2,3, Blake, IM2, Cai, ZL2, Luck, IJ2, Krausz, E4, Kobayashi, R,1,4 Reimers, JR1,5, and Crossley, MJ2 [email protected] 1 Shanghai University, Shanghai, China, 2 The University of Sydney, Australia, 3 OraInnova, Sydney, Australia, 4 The Australian National University, Canberra, Australia, 5 University of Technology Sydney, Australia The first new fundamental form of conformational isomerism since the discovery of pyrimidal inversion in 1961 is described. A new fundamental form of conformational isomerism based on bond-angle inversion is revealed through synthesis of four resolved stereoisomers 2a, 2b, 3a,and 3b of a transoid (BF)O(BF) quinoxalino[2,3- b’]porphyrin. These manifest structural relationships not describable within
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