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Part I, synthesis and properties of electron deficient porphyrins: Part II, synthesis of multidentate ligands. / Synthesis and properties of electron deficient porphyrins / Part II, synthesis of multidentate ligands / Synthesis of multidentate ligands / CUHK electronic theses & dissertations collectionJanuary 1999 (has links)
by Man Kin Tse. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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Synthesis and reactivity of new titanium hydrazido complexesTiong, Pei Jen January 2012 (has links)
This Thesis describes the synthesis and characterisation of titanium hydrazido(2-) and alkylidene hydrazido(2-) complexes and their reactivity towards unsaturated molecules. Exploration of the bonding in titanium hydrazido(2-) and alkylidene hydrazido(2-) complexes is performed through structural and computational studies. Chapter 1 introduces current Group 4 hydrazido chemistry in comparison to Group 4 imido and mid/late metal hydrazido examples. Current Group 4 alkylidene hydrazido chemistry is also described. Chapter 2 describes the synthesis, bonding and the novel reaction chemistry of titanium hydrazido(2-) half-sandwich complexes. Novel reactivity at the Ti=N, bond is presented with the mechanisms of some of these transformations probed by Density Functional Theory (DFT) calculations. Chapter 3 describes the novel reaction chemistry of Cp*Ti{MeC(Nipr)2} (NNMe2) in comparison to its imido and diphenyl hydrazido analogues. Novel reactivity at both Ti=N, and Na-N~ bonds is presented with the mechanisms of some of these transformations probed by Density Functional Theory (DFT) calculations. Chapter 4 describes the synthesis and characterisation of a new titanium alkylidene hydrazido(2-) complex. The bonding of the alkylidene hydrazido(2-) ligand is explored through structural and computational studies. Novel reactivity at Ti=N, and Na-N~ bonds is presented. Chapter 5 presents full experimental procedures and characterising data for the new complexes reported. CD Appendix contains .cif files for all new crystallographically characterised complexes described.
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Synthesis and Coordination Chemistry of Oxygen Rich Ligands: Bis(oxoimidazolyl)hydroborato, Tris(oxoimidazolyl)hydroborato and Tris(2-pyridonyl)methaneAl-Harbi, Ahmed Baker January 2014 (has links)
In Chapter One, the sodium salt of tris (2-oxo-1-t-butylimidazolyl) hydroborate, [To^But]Na, as an [O_3] donor ligand has been prepared. The yield for this reaction was low because there is a significant amount of side product in which the double bond of the oxoimidazole starting material is reduced. Treatment of sodium borohydride with bezannulated oxoimidazole at high temperature leads to the generation of the sodium salt of tris (2-oxo-1-R-methylbenimidazolyl) hydroborate in high yield, [To^RBenz]Na. These ligands have been prepared with different alkyl substituents, methyl, t-butyl and adamantyl, to achieve the desired steric environment. Furthermore, these benzannulated ligand have been used to synthesize a series [To^RBenz]Tl complexes, which exist as a discrete mononuclear complexes in the solid state. Finally, [To^RBenz]Tl complexes are more pyramidal than the sulfur counterpart, [Tm^RBenz]Tl, but less pyramidal than those in the tris (pyrazolyl)hydroborato counterpart, [Tp^R,R]]Tl.
In Chapter Two, the properties of [To^R] ligands have been evaluated versus related L_2X ligands. [To^R] ligands are substantially more sterically demanding than the corresponding [Tm^R] sulfur donor ligand and related [O_3] donor ligands. However, electronically, the [To^R] ligands exhibit weaker electron donating properties than other L_2X type ligands. Finally, the coordination chemistry of [To^R] ligands with various metal compounds has been briefly investigated. The synthesis of a new class of bidentate ligands has been detailed in Chapter Three. Namely the bis(2-oxo-1-t-butylimidazolyl)hydroborato and bis (2-oxo-1-alkylbenzimidazolyl)hydroborato, [Bo^But] and [Bo^RBenz], have been synthesized via the reaction of MBH_4 with two equivalents of the respective 2-imidazolone. Chelation of [Bo^But] and [Bo^MeBenz] to a metal center results in a flexible 8-membered ring that is capable of adopting a "boat-like" conformation that allows for secondary M—H—B interactions. Chapter Four describes the synthesis of [Bo^RBenz]_2Zr(CH_2Ph)_2and [To^RBenz]Zr(CH_2Ph)_3 with different alkyl substituents. Treatment of [To^ButBenz]Zr(CH_2Ph)_3 with ([PhNHMe_2][B{C_6F_5}_4]) in a coordinating solvent, Et_2O, generates {[To^ButBenz]Zr(CH2Ph)_2(OEt_2)}{B(C_6F_5)_4} which exhibit a very low activity for ethylene polymerization. However, a coordinatively unsaturated cationic zirconium alkyl complex was obtained by the treatment of ([PhNHMe_2][B{C_6F_5}_4]) with [To^ButBenz]Zr(CH_2Ph)_3 or [To^AdBenz]Zr(CH_2Ph)_3 which generate [To^ButBenz]Zr(CH_2Ph)_2[B(C_6F_5)_4 or [To^AdBenz]Zr(CH_2Ph)_2[B(C_6F_5)_4], respectively. Moderate activity for ethylene polymerization was obtained for t-butyl while high activity was obtained for the adamantyl derivatives. Finally, Chapter Five describes the synthesis of new oxygen-rich ligands, namely tris (2-pyridonyl)methane, [Tpom^R]H. They are obtained via the reaction of 2-pyridones with CHX_3 and K_2CO_3 in the presence of [Bu^n _4N]Br, followed by acid-catalyzed isomerization with camphorsulfonic acid. These compounds provide access to a new class of L_3X alkyl ligands that feature oxygen donors and are capable of forming metallacarbatranes, as exemplified by [Κ^4-Tpom^But]ZnOC6H4Bu^t. In addition, the [Tpom^But] ligand also allows isolation of a monovalent thallium alkyl compound, [Tpom^But]Tl, in which the Tl—C bond is long and has little covalent character.
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Part I, optimization of palladium catalyzed phosphination: Part II, syntheses of optically active As,N ligands and their metal complexes. / Optimization of palladium catalyzed phosphination / Part II, syntheses of optically active As,N ligands and their metal complexes / Syntheses of optically active As,N ligands and their metal complexesJanuary 2004 (has links)
Yu Michael. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 57-63). / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgments --- p.iii / Abbreviations --- p.iv / Abstract --- p.v / Chapter Part I - --- Optimization of Palladium Catalyzed Phosphination / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Background of Phosphine Synthesis --- p.1 / Chapter 1.2 --- Preparation of Phosphines --- p.4 / Chapter Chapter 2 --- Optimization of Phosphination of Aryl Bromides / Chapter 2.1 --- Additive Effect in Phosphination of Aryl Bromides --- p.14 / Chapter 2.2 --- Iodide Effect in Phosphination of Aryl Triflate --- p.25 / Chapter 2.3 --- Low Temperature Phosphination --- p.27 / Chapter 2.4 --- Conclusion --- p.29 / Chapter Part II - --- Synthesis of Optically Active As,N Ligands and Their Metal Complexes / Chapter Chapter 1 --- 3.1 Introduction --- p.30 / Chapter Chapter 2 --- Synthesis of Optically Active As,N Ligands and Their Metal Complexes / Chapter 4.1 --- "Synthesis of As,N Oxazolines" --- p.39 / Chapter 4.2 --- "Synthesis of As,N Oxazoline Transition Metal Complexes" --- p.41 / Chapter 4.3 --- Conclusion --- p.44 / Experimental --- p.45 / References --- p.57 / Appendix --- p.64
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Synthesis, structural characterization and reactivity of ruthenium complexes incorporating linked cyclopentadienyl-carboranyl ligands. / CUHK electronic theses & dissertations collectionJanuary 2006 (has links)
A new class of ruthenium-COD complexes containing carbon-bridged carboranyl-cyclopentadienyl (-indenyl or -fluorenyl) ligands was synthesized. These complexes showed a different reactivity in COD displacement reactions in comparison with the classical LRuCl(COD) (L = Cp, indenyl) complexes presumably due to the presence of sterically bulky and constrained organic-inorganic hybrid ligands. However, the COD ligands in these complexes can be replaced by bidentate tertiary phosphines, 2,2'-bipyridine, mono-phosphites with small cone angles, primary amines or N-heterocyclic carbene to give the corresponding COD displacement complexes. The ruthenium-amine complexes are much more labile than the ruthenium-COD ones. The amine ligands can be substituted by CH3CN to afford more active ruthenium-acetonitrile complex. / Reactions of dilithium salt of linked cyclopentadienyl-carboranyl ligands with 1 equiv of RuCl2(PPh3)3 in THF afforded the corresponding doubly-linked cyclopentadienyl-carboranyl ruthenium(II) hydride complexes. Such intramolecular coupling of a cyclopentadienyl with an o-carboranyl unit is driven by steric factors. Both carboranyl and phosphines with large cone angles are essential for such coupling reactions. The doubly-linked cyclopentadienyl-carboranyl compound was released from the corresponding ruthenium hydride complex by treatment with excess HBF 4·OEt2, followed by hydrolysis. This ligand is not accessible by any other known methods. / Reactions of the ruthenium-acetonitrile complex with SiMe3 substituted alkynes afforded mononuclear bis(vinylidene)metal or vinylvinylidenemetal, respectively, indicating that sterically demanding ancillary ligand and bulky alkynes are both important components to stabilize the above complexes. Treatment of the ruthenium-acetonitrile complex with internal alkynes afforded eta 4-Ru cyclobutadiene or ruthenacyclopentatriene complexes, respectively. Interestingly, interaction of ruthenium-acetonitrile complex with terminal aromatic alkynes gave ruthenium tricyclic complexes involving coupling reactions between Cp and alkynes. The possible reaction mechanism was proposed with the help of the DFT calculations. / Reactions of the ruthenium-amine complex with alkynes gave ruthenium aminocarbene or enamine complexes depending on the electronic properties of alkynes. Electron-rich alkynes gave aminocarbene complexes, whereas electron-deficient alkynes afforded enamine ones. The [eta5:sigma-Me 2C(C5H4)(C2B10H10)]Ru fragment remained intact during the reactions, which may play a role in these controlled reactions. / Sun Yi. / "May 2006." / Adviser: Zuowei Xie. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6398. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 157-177). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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Novel bulky fluorinated ligands for homogeneous catalysisFrew, Jamie J. R. January 2008 (has links)
A series of novel monodentate and bidentate phosphine ligands substituted with bulky tert-butyl and fluorinated aryl groups have been synthesised. Borane protection has proved to be an excellent method for easy synthesis and purification of bidentate ligands in some cases. However, several of the bulky fluorinated ligands do not form stable borane complexes leading to complications in the synthesis and purification of these compounds. By reaction with transition metal platinum and palladium precursors, it was possible to form dichloride complexes from the synthesised ligands, which were characterised by X-ray crystallography. The complexes were found to be effective catalysts for the hydroxycarbonylation of vinyl arenes (yields of up to 95 % with 3 mol% catalyst). An unsymmetrical bidentate complex (3.18) in combination with paratoluenesulfonic acid and LiCl promoters has given exceptional (for a diphosphine ligand) regioselectivity for the branched acid (98.7 % branched) in the hydroxycarbonylation of styrene. The role of the promoters has been found to be crucial in deciding the activity and selectivity in this reaction.
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Part I. Studies of octasubstituted Oxo(phthalocyaninato)titanium(IV) complexes: Part II. Dioxotungsten(VI) complexes with N2O2 and N2S2 tetradentate ligands. / Studies of octasubstituted Oxo(phthalocyanianto)titanium(IV) complexes / Part II. Dioxotungsten(VI) complexes with N2O2 and N2S2 tetradentate ligands / Dioxotungsten(VI) complexes with N2O2 and N2S2 tetradentate ligandsJanuary 1996 (has links)
by Wing-Fong Law. / Year shown on spine: 1997. / The "2" in the title is subscript. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 103-110). / ACKNOWLEDGMENT --- p.i / CONTENTS --- p.ii / LIST OF FIGURES --- p.v / LIST OF TABLES --- p.vii / ABBREVIATIONS --- p.viii / ABSTRACT --- p.x / Chapter I. --- STUDIES OF OCTASUBSTITUTED OXO(PHTHALOCYANINATO) TITANIUM(IV) COMPLEXES / Chapter 1. --- INTRODUCTION --- p.2 / Chapter 2. --- RESULTS AND DISCUSSION / Chapter 2.1. --- Preparation of Substituted Dicyanobenzenes and Dicyanonaphthalene --- p.9 / Chapter 2.2. --- Synthesis of Octasubstituted Oxo(phthalocyaninato)titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.12 / Chapter 2.3. --- "Solvent Effects on the UV-Vis Absorption Spectra of (2,3,9,10,16, 17,23,24-Octaheptylphthalocyaninato)oxotitanium(IV)" --- p.27 / Chapter 2.4. --- Aggregation of Octasubstituted Oxo(phthalocyaninato)titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.29 / Chapter 2.5. --- Electrochemical Studies of Octasubstituted Oxo(phthalocyaninato)- titanium(IV) and (Naphthalocyaninato)oxotitanium(IV) Complexes --- p.34 / Chapter 2.6. --- Reactions of Disubstituted Dicyanobenzenes with Zirconium(IV) Butoxide and Urea --- p.39 / Chapter 2.7. --- Conclusion --- p.40 / Chapter 3. --- EXPERIMENTAL SECTION / Chapter 3.1. --- Materials --- p.42 / Chapter 3.2. --- Physical Measurements --- p.42 / Chapter 3.3. --- "Preparation of l,2-Dicyano-4,5-diheptylbenzene" --- p.43 / Chapter 3.4. --- "Preparation of l,2-Dicyano-4,5-bis(pentyloxy)benzene" --- p.45 / Chapter 3.5. --- "Preparation of l,2-Dicyano-4,5-bis(alkoxymethyl)benzene" --- p.47 / Chapter 3.6. --- "Preparation of 3,6-Bis(butyloxy)-l,2-dicyanobenzene" --- p.49 / Chapter 3.7. --- "Preparation of 2,3-Dicyano-5,8-dihexylnaphthalene" --- p.50 / Chapter 3.8. --- Preparation of Octasubstituted Oxo(phthalocyaninato)titanium(IV) Complexes --- p.52 / Chapter 3.9. --- Preparation of Octasubstituted (Naphthalocyaninato)oxotitanium(IV) Complex --- p.57 / Chapter 3.10. --- Miscellaneous Syntheses --- p.58 / Chapter II. --- dioxotungsten(vi) complexes with n202 and n2s2 tetradentate ligands / Chapter 1. --- INTRODUCTION --- p.62 / Chapter 2. --- RESULTS AND DISCUSSION / Chapter 2.1. --- Preparation of Tetradentate Ligands --- p.75 / Chapter 2.2. --- Preparation of Dioxotungsten(VI) Complexes --- p.78 / Chapter 2.3. --- Electrochemical Studies of Dioxotungsten(VI) Complexes --- p.86 / Chapter 2.4. --- Oxo-transfer Properties of Dioxotungsten(VI) Complexes --- p.91 / Chapter 2.5. --- Conclusion --- p.94 / Chapter 3. --- EXPERIMENTAL SECTION / Chapter 3.1. --- Materials --- p.95 / Chapter 3.2. --- Physical Measurements --- p.95 / Chapter 3.3. --- Preparation of Tetradentate Ligands --- p.96 / Chapter 3.4. --- Preparation of Dioxotungsten(VI) Complexes --- p.100 / REFERENCES --- p.103 / APPENDIX A lH NMR spectra of Pc'TiOs --- p.111 / APPENDIX B 13C{1H} NMR spectra of octasubstituted PcTi compounds --- p.113 / APPENDIX C Mass spectra of octasubstituted PcTi and PcZr compounds --- p.118 / "APPENDIX D IR spectra of octasubstituted PcTi, NcTi and PcZr compounds" --- p.124 / APPENDIX E Cyclic voltammograms of octasubstituted PcTiOs and NcTiO --- p.131 / APPENDIX F Determination of aggregation number (n) and aggregation constant (K) --- p.136 / APPENDIX G 1H NMR spectra of dioxotungsten(VI) complexes --- p.138 / APPENDIX H 13C{1H} NMR spectra of dioxotungsten(VI) complexes --- p.140 / APPENDIX I LSI mass spectra of dioxotungsten(VI) complexes --- p.143 / APPENDIX J IR spectra of dioxotungsten(VI) complexes --- p.147 / APPENDIX K Crystallographic data of W02(L2-N202) (64) --- p.150 / APPENDIX L Kinetic data for the oxo-transfer reactions --- p.160
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Synthesis, structural characterization and reactivity of late transition metal complexes containing P,N-donor phosphine ligands. / CUHK electronic theses & dissertations collectionJanuary 2002 (has links)
Song Haibin. / "March, 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 137-151). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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A user-friendly synthesis of aryl arsines and phosphines.January 2001 (has links)
by Lai Chi Wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 63-68). / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgments --- p.iii / Abbreviations --- p.iv / Abstract --- p.v / Chapter Chapter 1 --- General introduction / Chapter 1.1 --- Background of phosphines and arsines ligands in metal catalysis --- p.1 / Chapter 1.2 --- Electronic effect of phosphines and arsines ligands in metal catalysis --- p.2 / Chapter 1.3 --- Synthesis of Aryl Phosphines --- p.7 / Chapter 1.4 --- Synthesis of Aryl Arsines --- p.9 / Chapter 1.5 --- The objective of this work --- p.11 / Chapter Chapter 2 --- Palladium catalyzed phosphination of aryl triflates / Chapter 2.1 --- Synthesis of aryl triflates --- p.12 / Chapter 2.2 --- Palladium catalyzed phosphination of aryl triflates --- p.15 / Chapter 2.3 --- Mechanistic studies of phosphination --- p.19 / Chapter Chapter 3 --- Palladium catalyzed arsination of aryl triflates --- p.22 / Chapter 3.1 --- Solvent and catalyst screening in palladium catalyzed arsination --- p.23 / Chapter 3 2 --- Stoichiometry of triphenylarsine --- p.24 / Chapter 3.3 --- Temperature effect of arsination --- p.25 / Chapter 3.4 --- Results of palladium catalyzed arsination --- p.26 / Chapter 3.5 --- Mechanistic studies of arsination --- p.28 / Chapter Chapter 4 --- Green chemistry approach 一 solventless phosphination and arsination / Chapter 4.1 --- Introduction to green chemistry --- p.30 / Chapter 4.2 --- Results of solventless phosphination --- p.31 / Chapter 4.3 --- Results of solventless arsination --- p.33 / Conclusion --- p.36 / Experimental --- p.37 / Reference --- p.63
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The synthesis, stability and structures of two novel macrocyclic ligands and their complexesBarnard, B. F. (Bernardus Francis) 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: This study comprises the synthesis and full characterization of two novel pendant-arm
donor macrocyclic ligands. The stability and structure of the complexes of these two
ligands with a series of metals ions [Mn(II), Co(II), Zn(II), Cd(II), Pb(II)], was
subsequently investigated.
The two parent macrocyclic ligands, 1,4,7-triazacyclodecane ([10]-ane-N3) and 1,4,8-
triazacycloundecane ([11]-ane-N3) were synthesized by means of the "direct
synthesis" method using tosylates as protecting groups. Pendant arms were then
added to the parent molecules to create hexadentate ligands. The two macrocyclic
ligands are asymmetric because of the different lengths of the carbon bridges between
the N-donor atoms of the rings. This feature gives the ligands the possibility to form
both five- and six-membered rings when coordinated to metal centers. The ligands
were fully characterized by means of NMR, mass spectrometry and elementalanalysis.
Melting points were also determined.
These two novel (triaza macrocyclic) ligands now complete the series between 9-ane-
N3 [with its 2-(S)-hydroxypropyl pendant arms] and 12-ane-N3 [with its 2-(S)-
hydroxypropyl pendant arms].
Protonation data of the ligands were determined using potentiometric titrations. The
respective protonation constants for both ligands in 0.1000 mol dm-3 NaNO3 are:
THTD log H
1 K = 9.176 and log H
2 K = 4.20
THTUD log H
1 K = 11.32 and log H
2 K = 5.87
A third protonation constant for both ligands (THTD and THTUD) was observed, but
the use of potentiometric methods could not produce reliable values at very low pH
values. stability constants of the new ligands with a series of metal ions were determined
using 0.1000 mol dm-3 NaNO3 as ionic medium. The log(K) values at 25°C with
THTD are:
Co(II) 22.93
Zn(II) 14.82
Cd(II) 19.38
Pb(II) 15.47
The log(K) values at 25°C with THTUD are:
Co(II) 17.52
Zn(II) 16.43
Cd(II) 18.05
Pb(II) 14.63
Very stable complexes were obtained with the larger Cd(II) ion when compared to
other similar ligands.
Crystal structures of some of the metal complexes were determined by X-ray
crystallography. Metal perchlorates were used in the preparation of the metal
complexes with THTD and THTUD, and various methods were utilized for the
crystallization process. The general formula for these complexes is [M(L)]2+·2(ClO4)-
where M=metal ion and L= neutral ligand. The bond lengths between the nitrogen
atom and the metal ion, and the oxygen atom and the metal ion are very much the
same in the respective crystal structures. This means that the metal ion lies almost
halfway between the nitrogen and the oxygen atoms. The Mn(II)-THTD complex
featured both a distorted octahedral and distorted trigonal prismatic configuration in
the unit cell. Co(II)-THTUD contains three molecules per unit cell all having a
distorted octahedral configuration. Zn(II)-THTUD crystallizes with six molecules per
unit cell. / AFRIKAANSE OPSOMMING: Hierdie studie behels die bereiding en volledige karakterisering van twee oorspronklike
hangkroonarmdonor makrosikliese ligande. Die stabiliteite en struktuur van komplekse van
hierdie twee ligande met ’n reeks metaalione [Mn(II), Co(II), Zn(II), Cd(II), Pb(II)] is
ondersoek.
Die twee basis ligande 1,4,7-triazasiklodekaan (10-ane-N3) en 1,4,8-triazasikloundekaan (11-
ane-N3) is gesintetiseer deur middel van die "direkte bereidingsmetode" met tosilate as
beskermingsgroepe. Hangkroonsyarms is aangeheg om die vorming van ’n heksadentate
ligand te bewerkstellig. Die twee makrosikliese ligande is asimmetries as gevolg van die
verskillende lengtes van die koolstofbrûe tussen die N-donor atome van die ringe. Hierdie
eienskap gee aan die ligande die vermoë om beide vyf- en seslidringe te vorm wanneer
komplekse gevorm word met metaalione. Die ligande is ten volle gekarakteriseer deur
middel van KMR-metings, massa-spektroskopie en element analise. Smeltpuntbepalings is
ook uitgevoer.
Die twee nuwe ligande voltooi nou die homoloë reeks tussen 9-ane-N3 [en sy 2-(S)-
hidroksiepropiel hangkroonarms] en 12-ane-N3 [en sy 2-(S)-hidroksiepropiel
hangkroonarms].
Protonasiedata van die ligande is bepaal deur middel van potensiometriese titrasie. Die
onderskeie protonasiekonstantes vir beide ligande in 0.1000 mol dm-3 NaNO3 is:
THTD log H
1 K = 9.176 en log H
2 K = 4.20
THTUD log H
1 K = 11.32 en log H
2 K = 5.87
’n Duidelik-waarneembare derde protonasiekonstante vir beide ligande (THTD en THTUD)
is opgemerk, maar potentiometriese metodes kon nie betroubare waardes lewer by die uiters
lae pH-lesings nie. Vormingskonstantes van die ligande met ’n reeks oorgangsmetale is bepaal deur gebruik te
maak van ’n 0.1000 mol dm-3 NaNO3 as ioniese medium. Die log(K) waardes by 25°C vir
THTD is:
Co(II) 22.93
Zn(II) 14.82
Cd(II) 19.38
Pb(II) 15.47
Die log(K) waardes by 25°C met THTUD is:
Co(II) 17.52
Zn(II) 16.43
Cd(II) 18.05
Pb(II) 14.63
Uiters stabiele komplekse is verkry met die groter Cd(II) ioon in vergelyking met ander
soortgelyke ligande.
Kristalstrukture van sommige van die metaalkomplekse is bepaal deur middel van X-straal
kristallografie. Metaalperchlorate is gebruik om metal komplekse met THTD en THTUD te
berei, en ’n verskeidenheid kristallisasieprosesse is gebruik. Die algemene formule vir
hierdie komplekse is [M(L)]2+·2(ClO4)- waar M = metaal ioon en L = neutrale ligand is. Die
bindingslengtes tussen die stikstof atoom en die metaalioon, en die suurstof atoom en die
metaalioon is nagenoeg dieselfde in die onderskeie kristalstukture. Dit beteken dat die
metaalioon ongeveer halfpad tussen die stikstof en die suurstof atome voorkom. Die Mn(II)-
THTD-kompleks vertoon beide oktahedrale - en trigonaal prismatiese konfigurasie in die
eenheidsel. Co(II)-THTUD het drie molekule per eenheidsel, almal verwronge oktahedrale
konformasies. Zn(II)-THTUD het gekristaliseer met ses molekule per eenheidsel.
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