Jozef Hodyl PhD Thesis - Theses - Flinders University

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Na +Figure 3.11 Generic structure depicting the sodium salt of a typical hydroxybenzoate guest species.H A and H B protons are shown for when the hydroxy group is in the para position.This set of 1 H NMR titration experiments was conducted in DMSO-d 6 by amethodology identical to that specified in the preceding binding constant study. The1 H NMR monitored titration experiments were run at a constant guest concentrationof 10 -3 M for benzoate, p-hydroxybenzoate, o-hydroxybenzoate, and 2,6-dihydroxybenzoate. This concentration was increased to 1.7 x 10 -3 for m-hydroxybenzoate due to difficulty in monitoring the chemical shifts of theresonances for this guest species. Benzoate and all the hydroxybenzoate based guestspecies exhibited chemical shifts, ∆δ max., of between 0.1 and 0.2 ppm and in all,excluding p-hydroxybenzoate, where the H B protons were followed, the chemicalshift monitored was from the resonance of the proton para to the carboxylate group.The chemical shifts for the resonance of this proton were always well removed fromthe host resonances.Each transference of the hydroxy group from para to ortho was expected to bringthe hydroxy group into a more favourable proximity and angular alignment for nonclassicalhydrogen bonding to the π-electron systems of the aromatic groups of thehost pendant-arms. This is depicted in Figure 3.12. It is well known that the strengthof hydrogen bonds is distance and angle dependent. 201 From the depiction of thehost-guest complexes represented in Figure 3.12, which is based on X-raydetermined structures, such as that in Figure 1.10, it is obvious that the potential for64
non-classical hydrogen bonding is geometrically possible in 78 and 79, but not in 77.77 78 79Figure 3.12 Schematic representation of three hydroxybenzoate host-guest complexes showing therange of potential hydrogen bonding interactions between the hydroxy hydrogen atomof the guest and an aromatic group of receptor 49 The ellipse shows the pathcircumscribed by precession of the hydroxy hydrogen atom around the O-Ar bond.Ab initio methods were used to model this phenomenon by Professor SadeghSalehzadeh of Bu-Ali-Sina <strong>University</strong> with an o-hydroxybenzoate guest included inthe cavity of receptor 29. 129 The structure obtained displayed the potential for ahydroxy group in the ortho position to participate in hydrogen bonding with anaromatic group from the host pendant-arms. 129 This series of guests was also to beused for inclusion studies with the silica immobilised receptor 94 in aqueousconditions and this will be discussed in Chapter 6.Prior to subjecting the hydroxybenzoate guests to 1 H NMR monitored titration ina search for enhanced binding strength attributable to non-classical hydrogenbonding a reference guest anion was needed. Sodium benzoate, shown in Figure3.13, was chosen for this purpose.Figure 3.13 Structure of sodium benzoate.65
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Silica Immobilised MetalIon Activat
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ABSTRACTImmobilisation of functiona
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DECLARATIONI certify that this thes
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EtOHGPDMSGPDMESGPSGPTSethanolglycid
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CHAPTER ONEINTRODUCTION
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The focus of this work was to prepa
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sequestering anions has proved to b
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ange of pH due to its high basicity
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nitrophenol or p-nitrophenolate wit
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It has been shown by NMR and crysta
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within the cavity of a p-tert-butyl
Page 25 and 26: 60 in 0.5% DMSO-MeCN (v/v). 82 The
Page 27 and 28: synthesised bi- tri- and tetra - π
Page 29 and 30: adopt a trans-III conformation, whe
Page 31 and 32: amide oxygen atoms on the pendant a
Page 33 and 34: apparent there is, nonetheless, evi
Page 35 and 36: However, hetero-N-substitution on t
Page 37 and 38: Si-OH +- OH SiO - + H 2 OFor surfac
Page 39 and 40: 35This material was obtained with a
Page 41 and 42: OOSiOHOROR OSiOHOOOSiOSiOSiOSiOSiOS
Page 43 and 44: Tetraaza metal complexes immobilise
Page 45 and 46: CHAPTER TWOSYNTHESIS OF MACROCYCLIC
Page 47 and 48: In addition, successful immobilisat
Page 49 and 50: 3233Figure 2.3Reaction of 3-(glycid
Page 51 and 52: The methodology chosen was adapted
Page 53 and 54: agreed with literature values. 109R
Page 55 and 56: XS HO O H61, n = 262, n = 3n+ClOSO6
Page 57 and 58: anhydrous ethanol, Scheme 2.7. The
Page 59 and 60: 75Figure 2.5 Structure of (S)-(-)-p
Page 61 and 62: metal ion coordination the pendant
Page 63 and 64: CHAPTER THREEGUEST MOLECULE INCLUSI
Page 65 and 66: 3.1 where K A is the association, o
Page 67 and 68: 0.5cχG∆δ∆δGbaχ GFigure 3.1S
Page 69 and 70: χG∆δ∆δGFigure 3.4 Job's Plot
Page 71 and 72: The downfield movement of the guest
Page 73 and 74: arm framework. The relative magnitu
Page 75: This phenomenon correlates well wit
Page 79 and 80: The full set of logK values obtaine
Page 81 and 82: such that they would indicate precl
Page 83 and 84: CHAPTER 4MODIFICATION OF THE SILICA
Page 85 and 86: Chemical modification of the silica
Page 87 and 88: GPTSGPDMESFigure 4.4Schematic depic
Page 89 and 90: GPS, 33, linker material with an ex
Page 91 and 92: free νOHτSiOHνSi-O-SiδH 2 Oasym
Page 93 and 94: 224, 225the surface silanol groups.
Page 95 and 96: esonances, the spectrum for Si-GPS-
Page 97 and 98: increase in surface coverage from t
Page 99 and 100: and, more so due to the larger size
Page 101 and 102: CHAPTER 5METAL ION UPTAKE STUDIES W
Page 103 and 104: Scheme 5.1 Metal(II) ion coordinati
Page 105 and 106: linker material, Si-GPS, 33; endcap
Page 107 and 108: [Cd(Trac)](ClO 4 ) 2 , 94, or Si-GP
Page 109 and 110: CHAPTER 6GUEST MOLECULE INCLUSION S
Page 111 and 112: and D-histidinate. Guest inclusion
Page 113 and 114: Table 6.2Percent inclusion data for
Page 115 and 116: contains two hydroxy groups in the
Page 117 and 118: methoxy group, as portrayed by the
Page 119 and 120: these guest molecules with receptor
Page 121 and 122: only about half of that taken up by
Page 123 and 124: Percent inclusion values for these
Page 125 and 126: Table 6.7Percent guest inclusion of
Page 127 and 128:
6.1.7 Guest inclusion studies with
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A1 3542Neutral GuestBAnionic GuestH
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A1 46 7532 Anionic Guest8BCHostHost
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extent, meta-positioned hydroxy gro
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δ obs (ppm)6.2146.2136.2126.2116.2
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CHAPTER 7EXPERIMENTAL7.1 General Ex
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inding constants (logK values) and
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delay time of 4 s. 13 C CPMAS NMR s
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C, -CH 2 - CH 2 OSO 2 ); 68.11 (1 C
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A solution of 69 (2.00 g, 10.1 mmol
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Bn, meta); 127.79 (1 C, Bn, para);
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added in a single portion. The mixt
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dioxane): δ 158.67 (1 C, C=O); 135
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1-(benzyloxycarbonyl)-4,7,10-tris-(
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1,4,7-tris-((S)-2-hydroxy-3-phenoxy
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1,4,7-tris(S)-2-hydroxy-3-[4-((2-(2
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1,4,7-tris(S)-2-hydroxy-3-[4-(2-(2-
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1-(2-hydroxypropyl)-4,7,10-tris-((S
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7.11 Preparation of the silica mate
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To a suspension of 33 (1.48 g, 1.1
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gel-like suspension that was cooled
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Si-GPS-Tri-Trac, 4545The title comp
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APPENDIX ABINDING CONSTANT DETERMIN
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1.01000.880δ obs (ppm)0.60.4logK =
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APPENDIX BDETERMINATION OF STOICHIO
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0.5χG∆δGFigure B.2χ GSimulated
Page 179 and 180:
13 C CPMAS NMR SPECTRA OF SOME HIGH
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Si-GPS-[Cd(Trac)(2,5-diydroxybenzoa
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REFERENCES
Page 185 and 186:
15. D. Tzalis and Y. Tor, Tetrahedr
Page 187 and 188:
42. A. P. Davis and R. S.Wareham, A
Page 189 and 190:
69. R. J. Bergeron, M. A. Channing
Page 191 and 192:
93. C. B. Smith, A. K. W. Stephens,
Page 193 and 194:
118. D. D. Dischino, E. J. Delaney,
Page 195 and 196:
144. X. Huang, X. Chang, Q. He, Y.
Page 197 and 198:
169. J. M. Klunder, T. Onami and K.
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197. K. A. Connors, Binding Constan
Page 201 and 202:
221. J. Blumel, J. Am. Chem. Soc.,
Page 203:
247. W. Likussar and D. F. Botz, An
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Jozef Hodyl PhD Thesis - Theses - Flinders University

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