Structural transformations related to organic solid-state reactions [Elektronische Ressource] : correlation studies of NMR and X-ray analysis / vorgelegt von Mujeeb Khan

Khan

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2008
• Nombre de lectures: 17
• Langue: English
• Poids de l'ouvrage: 3 Mo

Extrait

STRUCTURAL TRANSFORMATIONS RELATED
TO ORGANIC SOLID-STATE REACTIONS:
CORRELATION STUDIES OF NMR AND X-RAY
ANALYSIS


Dissertation
zur Erlangung des Grades


Doktor der Naturwissenschaften

im Promotionsfach Chemie



am Fachbereich Chemie,
Pharmazie und Geowissenschaften
der Johannes Gutenberg-Universität Mainz



vorgelegt von



MUJEEB KHAN

geboren in Hyderabad (Indien)


Mainz, 2008


D77(Dissertation Universität Mainz)
i

TABLE OF CONTENTS

1. INTRODUCTION .................................................................... 5

1.1. MOTIVATION ...................................................................................................... 5

2. ORGANIC SOLID-STATE REACTIONS ............................ 9

2.1. TOPOCHEMICAL CONTROL OF SOLID-STATE ORGANIC
REACTIONS................................................................................................................. 9
2.2. TOPOCHEMISTRY ........................................................................................... 11

2.2.1. Topochemical vs. nontopochemical processes ...................................................................... 11
2.2.2. Schmidt´s topochemical principle.......................................................................................... 11
2.3. SOLID SOLUTIONS 14

2.3.1. Examples of homogeneous and heterogeneous mechanisms ............................................... 15
2.4. SINGLE-CRYSTAL-TO-SINGLE-CRYSTAL TRANSFORMATION ........ 19

2.4.1. Significance of SCSC transformations .................................................................................. 20
2.4.2. Characterization techniques for SCSC transformations..................................................... 20
2.4.3. SCSC transformations using tail-irradiation........................................................................ 21
2.5. CRYSTAL ENGINEERING............................................................................... 25

2.5.1. Intermolecular forces in crystals ........................................................................................... 26
2.5.2. Hydrogen Bonding .................................................................................................................. 28
2.5.3. Cocrystals................................................................................................................................. 29
2.5.4. Supramolecular synthons....................................................................................................... 30

3. FUNDAMENTALS OF EXPERIMENTAL TECHNIQUES
...................................................................................................... 33

3.1. INTRODUCTION OF NMR ANALYSIS ......................................................... 33
3.2. BASICS OF NMR AND INTERACTIONS ...................................................... 33
3.3. ZEEMAN- INTERACTION............................................................................... 36
3.4. EFFECTS OF RADIO FREQUENCY FIELD (B ) ......................................... 38 1
3.5. CHEMICAL SHIELDING ................................................................................. 39
1Table of contents
_____________________________________________________________
3.6. DIPOLE-DIPOLE INTERACTION.................................................................. 41
3.7. MAGIC ANGLE SPINNING ............................................................................. 42
3.8. SINGLE-PULSE EXCITATION AND SINGLE PULSE DETECTION....... 43
3.9. CROSS POLARIZATION (CP)......................................................................... 44
3.10. INTRODUCTION OF X-RAY ANALYSIS.................................................... 46

3.10.1. Bragg’s law ............................................................................................................................ 46
3.10.2. Single crystal X-ray diffraction............................................................................................ 47
3.10.3. Powder diffraction ................................................................................................................ 49


4. TRANSIENT STATES IN [2+2] PHOTODIMERIZATION
OF CINNAMIC ACID ............................................................... 50

4.1. INTRODUCTION................................................................................................ 50
4.2. CONFORMATION OF CARBOXYL GROUP ............................................... 52
134.3. SOLID-STATE C-CPMAS NMR APPLICATION....................................... 52
4.4. REPLACING CARBOXYL ACID MIOETY................................................... 55
4.5. DYNAMICS OF HYDROGEN BONDS............................................................ 57
4.6. STRUCTURAL CORRELATIONS................................................................... 58
4.7. DEUTERIUM NMR MEASUREMENTS......................................................... 59
4.8. HIGH TEMPERATURE X-RAY ANALYSIS ................................................. 61
4.9. SYNPLANAR Vs. ANTIPLANAR CONFORMATION ................................. 61
4.10. AB INITIO COMPUTATIONS........................................................................ 65
4.11. CONCLUSIONS ................................................................................................ 65
4.12. EXPERIMENTAL............................................................................................. 66

4.12.1. Synthesis of truxillic acid...................................................................................................... 66
4.12.2. Syf methyl ester of truxillic acid............................................................................ 67
4.12.3. Solid-State NMR measurment 68
4.12.4. Solution NMR and mass....................................................................................................... 68
4.12.5. DFT-based chemical shift calculations................................................................................ 68
4.12.6. Single Crystal X-ray Analysis .............................................................................................. 69

5. O-H···N HETEROSYNTHON: A ROBUST
SUPRAMOLECULAR UNIT FOR CRYSTAL
ENGINEERING ......................................................................... 70

2Table of contents
_____________________________________________________________
5.1. INTRODUCTION................................................................................................ 70
5.2. HYDROGEN BOND MEDIATED SELF ASSEMBLY .................................. 72
5.3. CO-CRYSTALLIZATION OF RESORCINOLS AND MONOPYRIDINES
LEADING TO THE DESIRED STRUCTURES..................................................... 74
5.4. CO-CRYSTALLIZATION OF RESORCINOLS AND DIPYRIDINES 75
5.5. CO-CRYSTALLISORCINOLS WITH MONO- OR
DIPYRIDINES LEADING TO THE UNDESIRED STRUCTURES.................... 77
5.6. MOLECULAR RECOGNITION OF PHOTOREACTIVE CONJUGATED
DIPYRIDINES ............................................................................................................ 80
5.7. MONITORING THE STRUCTURAL CHANGES BY X-RAY ANALYSIS 83
5.8. TILTING AND DEFORMATION OF PYRIDYL AND PHENYL RINGS .. 86
5.9. CONCLUSIONS .................................................................................................. 89
5.10. Experimental Section......................................................................................... 90

5.10.1. General Details ...................................................................................................................... 90
5.10.2. Preparations of photoreactive conjugated dipyridines...................................................... 90
5.10.3. 2,6-Bis[(E)-2-(4-pyridyl)ehtenyl]naphthalene (bpen)......................................................... 91
5.10.4. Crystal Preparation .............................................................................................................. 91

6. PROBING STRUCTURAL TRANSFORMATIONS IN
2(BPE):2(RES) HETEROSYNTHON BY NMR METHODS
IN THE SOLID-STATE............................................................. 93

6.1. INTRODUCTION................................................................................................ 93
6.2. MOLECULAR CONFORMATION OF RESORCINOL ............................... 95
6.3. MOLECULAR CONFORMATION OF BPE................................................... 99
6.4. MOLECULAR SPECIFICITY OF THE O-H···N HERETOSYNTHON.... 101
6.5. NEW POLYMORPH OF 2(BPE):2(RES) MONOMER................................ 102
6.6. MOLECULAR CONFORMATION OF 2(BPE):2(RES) MONOMER....... 104
6.7. OBSERVATION OF A NEW POLYMORPH OF 2(BPE):2(RES) DIMER107
6.8. THERMAL ANALYSIS OF 2(BPE):2(RES) DIMER ................................... 109
6.9. REMOVAL OF TEMPLATE FROM 2(BPE):2(RES) DIMER ................... 110
6.10. CONCLUSIONS .............................................................................................. 113
6.11. EXPERIMENTAL...............