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(III) Complexes George Joseph Samuels Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1979 A new series of chelated organochromium (III) complexes George Joseph Samuels Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Inorganic Chemistry Commons Recommended Citation Samuels, George Joseph, "A new series of chelated organochromium (III) complexes " (1979). Retrospective Theses and Dissertations. 6621. https://lib.dr.iastate.edu/rtd/6621 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. 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Universify Microfilms International 300 N, ZEEB ROAD, ANN ARBOR, Ml 48106 18 BEDFORD ROW, LONDON WCl R 4EJ, ENGLAND 7916213 SAMUELS, GEORGE JOSEPH A NEW SERIES OP CHELATED ORGANOCHRDMIUM(111) COMPLEXES. IOWA STATE UNIVERSITY, PH.D., 1979 Universi^ MicrOTlms International 300 n. hoad. ann arbof^. mi 48106 A new series of chelated organochromlum(III) complexes George Joseph Samuels A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Department; Chemistry Major: Chemistry (Inorganic-Organic) Approved: Signature was redacted for privacy. Charge of Major Work Signature was redacted for privacy. artment Signature was redacted for privacy. Po3 Graduate College Iowa State University Ames, Iowa 1979 11 TABLE OP CONTENTS Page PART I. THE KINETICS AND MECHANISM OP FORMATION OP ORGANOCHROMIUM(III) CHELATES PROM CHROMIUM(II) CHELATE AND ORGANIC HALIDES 1 INTRODUCTION 2 HISTORICAL DEVELOPMENT 4 EXPERIMENTAL SECTION 24 Materials 2H Preparation of CrClg'^HgO 24 Preparation of [15]aneNh-l,4,8,12-tetraaza- cyclopentadecane 25 Halldes 26 Solvent preparation 26 Cr([15]aneN^)^"^ 27 Other materials 28 Methods 28 Analyses 28 Separation and purification of reaction mixtures 29 Isolation of organochromlum salts 30 Spectra 31 Gas Chromatography 32 Electrochemistry 33 Stolchlometry 34 Kinetics 35 Results 38 Characterization of Cr([15]aneN^)^^ 38 Characterization of the Products of Reaction of Cr([15]aneN^) with Organic Halldes 39 General description 39 Ill Characterization of the Inorganic Reaction Products 42 Characterization of the Organochromlum Species 49 Characterization of the Reaction of Organic Halldes with Cr([15]aneN^)^^ 60 Gemlnal Halldes and their Reaction with Cr([15]aneNy)2+ 63 Radical Intermediates and the Rate of Radical Capture 64 Kinetics 66 Activation Parameters 77 DISCUSSION 85 PART II. REACTIONS OF SIGMA BONDED ORGANOCHROMIUM(III) CHELATE COMPLEXES WITH MERCURY(II) ELECTROPHILES 97 INTRODUCTION 98 EXPERIMENTAL 101 Preparation of Organochromlum Compounds 101 n-Alkyl([15]aneN2|) chromlum(III) complexes 101 Secondary and benzylCr(L)complexes 102 l-Adamantylchromlum([15]aneN^)^^ 103 Mercury compounds 103 Other materials 104 Methods 104 Analyses 104 Spectra 106 Stolchlometry 106 Kinetics 107 iv RESULTS 110 Characterization 110 RCr([15]aneN^)2+ 110 Organomercury(II) products 110 Characterization of Reactions 110 Kinetics 111 Preliminary experiments 111 Kinetics of reactions 116 Kinetics of CH^Hg^ reactions 124 Activation Parameters - Isokinetic Relationships 128 DISCUSSION 145 PART III. THE CRYSTAL STRUCTURE OP [trans- CHLOROAQUO(1,4,8,12-TETRAAZACYCLO- PENTADECANE)CHROMIUM(III)DIIODIDE- DIHYDRATE 158 INTRODUCTION 159 EXPERIMENTAL l60 Preparations l60 [t^ClCr([15]aneN^)H20]l2'2H20 l60 Crystal data 160 Collection and Reduction of X-ray Intensity Data 162 Solution and Refinement l64 DESCRIPTION AND DISCUSSION I69 LITERATURE CITED 175 ACKNOWLEDGEMENTS 182 V LIST OP TABLES Page Table I-l. Relative rates of reduction of alkyl II halldes by the Cr (en) reagent at 25° 13 Table 1-2. Perfluoroallcy.lchromlum chelate 19 complexes Table 1-3. Rate constants for reduction of alkyl Iodides by Co(CN)^~ at 25°, ref. 40 2 22 Table 1-4. Spectral parameters for the various trans-XCr([ 15]aneN)H ^ complexes 48 Table 1-5. Spectral parameters for various 2 + tran3-RCr([15]aneN^) complexes 59 Table 1-6. Kinetic data for the reactions of 2 4- Cr([15]aneN||) with organic mono- halldes. Conditions 1:1 v/v ;t-butanol/waterJ y = 0.20 M (LI ), T = 25° 70 Table 1-7. Summary of the kinetic data for the reactions of Cr([15]aneN^)^^ with gemlnal dlhalldes and pseudo hallde. Conditions; Solvent 1:1 v/v t-butanol/water, y = 0.20 M, T = 25° 74 Table 1-8. Temperature dependence of the reaction rate of EtBr with Cr([15]aneN^)^* 78 Table 1-9. Temperature dependence of the reaction rate of EtI with Cr([15]aneN^)^'^ 80 vl Table I-IO. Temperature dependence of the reaction rate of PhCHgCl with Cr([15]aneN^)2+ 82 Table I-ll. Summary of the kinetic data for the reactions of Cr([15]aneN^)^^ with organic monohalldes. Conditions: Solvent 1:1 v/v t-butanol/water, y = 0.20 M, T = 25.0° 88 Table 1-12. A comparison of reaction rates of RX with reduced metal species (dm^ mol~^ s~^) 91 Table 1-13. Summary of activation parameters for the reaction of organic halldes with reducing metal complexes 95 Table II-l. Kinetic data for the reactions of Hg2+ with RCr([15]aneNy)2+ complexes, R = primary alkyls. Conditions: [H^] = 0.25 M, y = 0.50 M, T = 25.0° 125 Table II-2. Kinetic data for the reactions of Hg^^ with RCr([15]aneN^)^^ complexes, R = secondary and tertiary alkyls. Conditions: [H+] = 0.17 M, y = 1.46 M, T = 25.0° 127 Table II-3. Kinetic data for the reaction of CH^Hg"*" with RCr([15]aneN^)2+. Conditions: [H^] = 0.25 M, y = 0.50 M, T = 25.0° 130 vil Table II-4. Temperature dependence of the rate of reaction of with ethylCr(L). Conditions: [H^] = 0.25 M, M = 0.50 M 135 Table II-5. Temperature dependence of the rate of reaction of with n-propylCr(L) , Conditions: [H*] = 0.25 M> y = 0.50 M 136 Table II-6. Temperature dependence of the rate of reaction of Hg^"*" with n-butylCr(L)^*, Conditions: [H^] = 0.25 M, IJ = 0.50 M 137 Table II-7. Temperature dependence of the rate of reaction of Hg^"*" with n^-pentylCr(L), Conditions: [H*] = 0.25 M, y = 0.50 M 138 Table II-8. Temperature dependence of the rate of reaction of Hg^"*" with benzylCr(L), Conditions: [H^] = 0.25 M, y = 0.25 M 139 Table II-9. Activation parameters for the reaction of with R-Cr([15]aneN^)2+ 142 2+ Table 11-10, Summary of reaction rates for Hg with RCr(L)2+ Conditions [H"] = 0.25 M, y = 0.50 M, T = 25.0° 147 vlll Table 11-11. Summary of reaction rates for CH^Hg with RCr(L)^*. Conditions: [H+] = 0.25 M, y = 0.50 M, T = 25.0 Table 11-12. Summary of reaction rates of Hg(II) with organochromlum cations, q — 1 — 1 k/dmrmol" s~ . Conditions: [H+] = 0.25 M, y = 0.50 M, T = 25.0 Table 11-13. Relative rate trends, %%/%%%* various 3^2(open) reactions of metal alkyls, R = aliphatic Table II-14 Summary of the activation parameters for the reaction of Hg(II) with organochromlum cations. Conditions [H+] = 0.25 M, y = 0.50 M Table III-l. Final atomic positions Table III-2. Anisotropic thermal parameters (xlO^ Table III-3. Bond lengths (X) for ClCr(L)H20^"*" Table III-4. Bond angles (degrees) Table III-5. Comparison of bond distances ix LIST OF FIGURES Page Figure I-l. The cyclic voltammagram for the Cr(L)3*/Cr(L)^^ couple 40 Figure 1-2. The electronic spectrum of Cr([15]aneN^)2+ in 1:1 t^BuOH/HgO ill Figure 1-3. The electronic spectrum of trans-ClCrÇLÏH^O^* Figure 1-4. The electronic spectrum of trans-BrCr(L)HoO^"'" ^5 Figure 1-5.
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