INORGANIC SEMINAR ABSTRACTS .Univlh^Ii X Y, ILLINOIS at U "* ~' PMGN UNIVERSITY of 1979-1980 ' - ILLINOIS LIBRARY at URBANA-CHAMPAIGN CHEMISTRY Page
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UNIVERSITY OF ILLINOIS LIBRARY AT IP&ANA-CHAMPA1GN The person charging >^ ^bra'vlrom below. i«test DateWMiv. stamped LateST h„-u* ore reasons ond from Th.lt, mo.no.ion. dism issa. ac.ion "^"'JJland may for disciplinary the University- 333-8400 .aUTeiephoneC"-' 3 To renew ^^hamPA^ L161— O-1096 Digitized by the Internet Archive in 2012 with funding from University of Illinois Urbana-Champaign http://archive.org/details/inorganicsemi79808384univ UNIVERSITY OF ILLINOIS I no TABLE OF CONTENTS JAN 7 1 INORGANIC SEMINAR ABSTRACTS .UNIVLh^ii X y, ILLINOIS AT U "* ~' PMGN UNIVERSITY OF 1979-1980 ' - ILLINOIS LIBRARY AT URBANA-CHAMPAIGN CHEMISTRY Page PART 1: STRUCTURAL, SPECTRAL, AND MAGNETIC PROPERTIES 1 OF A COPPER (II) BIMETALLOMER. PART 2: THERMODYNAMIC, ESR, AND HYDROGEN BONDING STUDIES OF COBALT DIOXYGEN COMPLEXES - Kenneth A. Leslie - A THERMODYNAMIC STUDY OF METAL CARBOXYLATES , 4 John R. Long ORGANO Os 3 CLUSTER CHEMISTRY: HYDRIDO-CH 3 , -CH 2 , -CH, 7 AND RELATED COMPOUNDS R. B. Calvert THERMODYNAMIC CHARACTERIZATION OF Ni(tfacDPT) - 9 Robert G. Mayer COOPERATIVITY AND SPIN-DYNAMICS IN IRON (III) SCHIFF- 11 BASE COMPLEXES EXHIBITING SPIN-CROSSOVER PHASE TRAN- SITION - Muin Shawki Haddad APPLICATIONS OF FOURIER TRANSFORM EPR TO INORGANIC 13 CHEMISTRY - Barry B. Corden NITROGEN-14 NUCLEAR QUADRUPOLE DOUBLE RESONANCE 17 STUDIES OF NITROGEN BASES - William L. McCullen ONE DIMENSIONAL MAGNETIC SYSTEMS - Warren L. Nehmer 2 CHEMOPREVENTION OF CANCER: ANTICANCER EFFECTS OF 22 SELENIUM AND SELENITE - Mary M. Fox PARAMAGNETIC COMPLEXES OF BINUCLEATING LIGANDS - 2 5 Russell C. Long THE SYNTHESIS, REACTIVITY, AND ELECTRONIC CHARACTER- 2 8 IZATION OF NEW LOW VALENT TITANIUM COMPLEXES - David R. Corbin SYNTHESIS, CHARACTERIZATION, AND REACTIVITY OF 30 ELECTRON RICH TRANSITION METAL ORGANOMETALLIC COMPLEXES - James J. Welter - v u ^University of Illinois • Cable of Contents Inorganic Seminar Abstracts 1979-80 Page 2 Page SYNTHETIC AND STRUCTURAL CHEMISTRY OF XENON - 3 2 Cynthia Smith THE METAL CATALYZED INTERCONVERSION OF NORBORNADIENE 34 AND QUADRICYCLANE - Edith Landvatter TWO-DIMENSIONAL NMR - INORGANIC APPLICATIONS - 37 Richard Cosmano PHOTOCHEMICAL WATER SPLITTING - James Goodale 40 MACROCYCLIC LIGANDS AND THE TEMPLATE EFFECT - 42 John E. Hoots TRIPLE DECKER SANDWICH COMPLEXES - Debra Wrobleski 46 GROUP VIII METAL COMPLEX ACTIVATION OF 2 TOWARDS 49 ORGANIC SUBSTRATES - Eric Nyberg RECENT ORGANO-LANTHANIDE AND -ACTINIDE CHEMISTRY - 51 Paul F. Schubert THE CHEMISTRY OF S^Nit - David Lesch 54 THE PHOTOCHEMICAL REACTION OF Re 2 (CO)i WITH H 2 AND 56 RELATED SYSTEMS - David Gard ELECTRON ENERGY LOSS SPECTROSCOPY AND ITS APPLICABILITY 58 TO INORGANIC SYSTEMS - Dean A. Oester SILICA SUPPORTED CHROMIUM CATALYSTS FOR OLEFIN 6 POLYMERIZATION - Michael A. Urbancic THE CHEMISTRY OF Cp 2 ZrL 2 - Peter Woyciesjes 63 APPLICATIONS TO INORGANIC CHEMISTRY OF MAGNETIC NUCLEAR 6 5 SPECTROSCOPY - Michelle Cohn .u University of Illinois Table of Contents Inorganic Seminar Abstracts 1979-80 Page 2 Page SYNTHETIC AND STRUCTURAL CHEMISTRY OF XENON - 32 Cynthia Smith THE METAL CATALYZED INTERCONVERSION OF NORBORNADIENE 34 AND QUADRICYCLANE - Edith Landvatter TWO-DIMENSIONAL NMR - INORGANIC APPLICATIONS - 37 Richard Cosmano PHOTOCHEMICAL WATER SPLITTING - James Goodale 40 MACROCYCLIC LIGANDS AND THE TEMPLATE EFFECT - 42 John E. Hoots TRIPLE DECKER SANDWICH COMPLEXES - Debra Wrobleski 46 GROUP VIII METAL COMPLEX ACTIVATION OF 2 TOWARDS 49 ORGANIC SUBSTRATES - Eric Nyberg RECENT ORGANO-LANTHANIDE AND -ACTINIDE CHEMISTRY - 51 Paul F. Schubert THE CHEMISTRY OF S*KU - David Lesch 54 THE PHOTOCHEMICAL REACTION OF Re 2 (CO)io WITH H2O AND 56 RELATED SYSTEMS - David Gard ELECTRON ENERGY LOSS SPECTROSCOPY AND ITS APPLICABILITY 58 TO INORGANIC SYSTEMS - Dean A. Oester SILICA SUPPORTED CHROMIUM CATALYSTS FOR OLEFIN 60 POLYMERIZATION - Michael A. Urbancic THE CHEMISTRY OF Cp 2 ZrL 2 - Peter Woyciesjes 63 APPLICATIONS TO INORGANIC CHEMISTRY OF MAGNETIC NUCLEAR 65 SPECTROSCOPY - Michelle Conn PHOTOCHEMISTRY OF TRANSITION METAL CARBONYL CLUSTERS - 67 Thomas R. Herrinton BIG BIRD - Michael J. Desmond 69 SYNTHESIS OF MIXED TRANSITION METAL CLUSTERS OF OSMIUM 71 AND RHENIUM VIA METAL HYDRIDE COUPLING REACTIONS - Greg Pearson SYNTHESIS AND REACTIONS OF tt-CYCLOPENTADIENYLCARBONYL- 73 IRIDIUMDIHYDRIDE and tt-CYCLOPENTADIENYLDICARBONYL- RHENIUMDIHYDRIDE - Paul C. Adair . Part 1: STRUCTURAL, SPECTRAL, AND MAGNETIC PROPERTIES OF A COPPER (II) BIMETALLOMER Part 2: THERMODYNAMIC, ESR, AND HYDROGEN BONDING STUDIES OF COBALT DIOXYGEN COMPLEXES Kenneth A. Leslie Final Seminar July 10, 1979 Part 1 An earlier X-ray crystallographic investigation [1] indi- cated that the complexes Cu(salen) and Co(hfac) 2 reacted to form the bimetallomer Cu (salen) Co (hfac) 2 in which the oxygen donor atom of salen was simultaneously coordinated to copper and cobalt. In the course of characterizing this compound and others of the form M (salen) M' (hfac) 2 [2], it was found that they had good solubility in CH 2 C1 2 , unlike many other binuclear com- plexes. Thus, a variety of physical methods could be used to study the effect that one metal center has on the chemistry of the second metal center. The bimetallomer Cu (salen) Cu (hfac) 2 was prepared and since it contains two different copper (II) environments (six-coordinate and four-coordinate) , magnetic susceptibility and ESR spectral studies were undertaken in order to characterize the system. Variable temperature magnetic susceptibility measurements indi- cate an antiferromagnetic exchange interaction with a coupling -1 constant, J, between the copper (II) centers of -20.4 cm . This value of J was relatively small compared to other symmetric copper (II) bimetallomers and different from the value expected from theory [3,4] for a symmetric bimetallomer (with a bridge angle corresponding to that found in the copper-cobalt adduct) In order to explain these results, a single crystal X-ray diffraction study was carried out. The compound crystallizes in the triclinic space group PI with four molecules in the unit cell. The reduced cell parameters are a = 17.03(4) A, b = 19.11(4) A, c = 9.89(2) A, a = 96.58(11)°, 3 = 100.10(16)°, y = 107.70(13)°. The structure was refined by full-matrix least- squares methods to a weighted R factor of 0.074 for data with FQ > 3a F . The structural results indicate that the reduced value of J is due to the low symmetry of the bridge area which allows for only one phenolic oxygen to participate in the superexchange pathway [5]. The investigation of a related system appears to give similar results [6] . Part 2 There has been a great amount of work in the literature dealing with the ability of many tetradentate and pentadentate cobalt(II) complexes to reversibly bind dioxygen [7,8]. Much of this research was in part due to a desire to understand the factors involved in the binding of dioxygen in biological systems. Part 1: STRUCTURAL, SPECTRAL, AND MAGNETIC PROPERTIES OF A COPPER (II) BIMETALLOMER Part 2: THERMODYNAMIC, ESR, AND HYDROGEN BONDING STUDIES OF COBALT DIOXYGEN COMPLEXES Kenneth A. Leslie Final Seminar July 10, 1979 Part 1 An earlier X-ray crystallographic investigation [1] indi- cated that the complexes Cu(salen) and Co(hfac) 2 reacted to form the bimetallomer Cu (salen) Co (hfac) 2 in which the oxygen donor atom of salen was simultaneously coordinated to copper and cobalt. In the course of characterizing this compound and others of the form M (salen) M* (hfac) 2 [2], it was found that they had good solubility in CH 2 C1 2 , unlike many other binuclear com- plexes. Thus, a variety of physical methods could be used to study the effect that one metal center has on the chemistry of the second metal center. The bimetallomer Cu (salen) Cu (hfac) 2 was prepared and since it contains two different copper (II) environments (six-coordinate and four-coordinate) , magnetic susceptibility and ESR spectral studies were undertaken in order to characterize the system. Variable temperature magnetic susceptibility measurements indi- cate an antiferromagnetic exchange interaction with a coupling -1 constant, J, between the copper (II) centers of -20.4 cm . This value of J was relatively small compared to other symmetric copper (II) bimetallomers and different from the value expected from theory [3,4] for a symmetric bimetallomer (with a bridge angle corresponding to that found in the copper-cobalt adduct) In order to explain these results, a single crystal X-ray diffraction study was carried out. The compound crystallizes in the triclinic space group Pi with four molecules in the unit cell. The reduced cell parameters are a = 17.03(4) A, b = 19.11(4) A, c = 9.89(2) A, a = 96.58(11)°, 3 = 100.10(16)°, y = 107.70(13)°. The structure was refined by full-matrix least- squares methods to a weighted R factor of 0.074 for data with FQ > 3ap. The structural results indicate that the reduced value of J is due to the low symmetry of the bridge area which allows for only one phenolic oxygen to participate in the superexchange pathway [5], The investigation of a related system appears to give similar results [6] . Part 2 There has been a great amount of work in the literature dealing with the ability of many tetradentate and pentadentate cobalt(II) complexes to reversibly bind dioxygen [7,8]. Much of this research was in part due to a desire to understand the factors involved in the binding of dioxygen in biological systems . The cobalt dioxygen adducts were considered as models since they have one unpaired electron, allowing their electronic structure to be probed using- ESR spectroscopy. In addition, potential industrial applications were recognized leading to the use of cobalt (II) complexes as catalysts for selective and controlled oxidations of organic substrates, most notably phenols [9] Previous studies have elucidated some of the factors involved in the binding of dioxygen to the porphyrin Co(PPIXDME) [10]. It was felt that the Co(PPIXDME) results would provide a foundation for examining the thermodynamic and electronic properties of cobalt (II) Schiff-base complexes.