Metal complexes of n (7 hydroxyl 4 methyl 8 coumarinyl) amino acid, n (2 pyridylmethyl) amino acid and related ligands synthesis, structural, photophysical and gelation properties

METAL COMPLEXES OF N-(7-HYDROXY-4-METHYL-8-
COUMARINYL)-AMINO ACID, N-(2-PYRIDYLMETHYL)-
AMINO ACID AND RELATED LIGANDS: SYNTHESIS,
STRUCTURAL, PHOTOPHYSICAL AND GELATION
PROPERTIES













LEONG WEI LEE
(B. Sc.,Universiti Teknologi Malaysia)





A THESIS SUBMITTED
FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
DEPARTMENT OF CHEMISTRY
NATIONAL UNIVERSITY OF SINGAPORE
2008

I

Acknowledgement

I would like to express my sincerest appreciation to my supervisor, Professor
Jagadese J. Vittal for his guidance, continuous support, encouragement and inspiration
during these years. His valuable guidance helped me to proceed in the course of this
project. His intellectual support and encouragement were indispensable for completion in
this project.
I am grateful to my collaborator, Professor Stefan Kasapis and Ms. Koh Lee Wah
for rheological studies. I am thankful to Dr. Xu Qing-Hua and Mr. Lakshminarayana
Polavarapu for fluorescence lifetime measurements. Special thanks to Professor Vivian
Wing-Wah Yam and Mr. Anthony Yiu-Yan Tam, The University of Hong Kong, for the
photophysical studies. Their help and contribution were essential in this work.
I am thankful to all my group members for their moral support and advices.
Particularly, I would like to express my gratitude to Dr. Ng Meng Tack, Dr. Tian Lu, Dr.
Bellam Sreenivasulu, Dr. Sudip K. Batabyal and Dr. Mangayarkarasi Nagarathinam for
their invaluable support, suggestions and motivation. Special thanks to Dr. Sudip K.
Batabyal for his inspiration and contribution in the hydrogel projects.
Deeply thanks to all the staffs in CMMAC laboratories and general office for their
assistance during these years. I would like to thank Associate Professor Jagadese J. Vittal,
Ms. Tan Geok Kheng and Professor Koh Lip Lin for their help in X-ray crystallography
data collection and structure solution.
I would like to thank all of my friends especially Jiang Jianming, Han Yuan and
Pauline Ong for their moral support. I am grateful to my family for their love and
understanding. Their encouragement is great motivation to me all the times.
Lastly, I thank National University of Singapore for research scholarship.

II






Declaration

This work described in this thesis was carried at the Department of Chemistry,
National University of Singapore from 10
th
Jan 2005 to 31
st
Dec 2008 under the
supervision of Associate Professor Jagadese J. Vittal.

All the work described herein is my own, unless stated to the contrary, and it has
not been submitted previously for a degree at this or any other university.



Leong Wei Lee
31
st
December 2008

III
Table of Contents

Acknowledgements I
Declaration II
Table of Contents III
Abbreviations VIII
Summary X
List of Compounds Synthesized XII
List of Figures XXI
List of Tables XXVIII

Publications and Presentations XXX

Chapter 1 Introduction
1
1-1. Supramolecular chemistry and Crystal engineering 2
1-2. Supramolecular interactions 3
1-2-1. Hydrogen bonds 3
1-2-2.
p
-
p
interactions
5
1-3. Schiff base and reduced Schiff base from amino acids 6
1-3-1. N-(2-hydroxybenzyl)-amino acids 6

1-3-2. N-(2-pyridylmethyl)-amino acid ligands 14
1-4. Complexes of coumarin derivatives 19
1-5. Supramolecular gels 20
1-5-1. Hydrogels 21
1-5-2. Metallo- and coordination polymeric gels 22
1-6. Scope of the current investigation 29

Chapter 2 Coordination Chemistry of Metal Complexes of Calcein Blue:
Monomeric, Ion-pair and Polymeric Complexes
32
Preface to Chapter 2 33



IV
Part A Synthesis and Characterization of Metal Complexes of Calcein
Blue: Formation of Monomeric, Ion-pair and Coordination Polymeric
Structures
34
2-A-1. Introduction 35
2-A-2. Results and discussion 37
2-A-2-1. Synthesis 37
2-A-2-2. Description of crystal structures 37
2-A-2-2-1. [Cu(Hmuia)(H
2
O)]
×
CH
3
OH

×
2H
2
O, IIA-1
37
2-A-2-2-2. [Ni(Hmuia)(H
2
O)
2
]
×
2H
2
O, IIA-2
39
2-A-2-2-3. [Mn(H
2
O)
6
][Mn
2
(muia)
2
(H
2
O)
2
]
×
2CH

3
CN, IIA-3
and [Mg(H
2
O)
6
][Mg
2
(muia)
2
(H
2
O)
2
]×2CH
3
CN, IIA-4

42
2-A-2-2-4. [Mn(H
2
O)
4.5
(CH
3
OH)
1.5
]
2
[{Mn

2
(muia)
2
}-
{Mn
2
(muia)
2
(H
2
O)
2
}]×5H
2
O, IIA-5
45
2-A-2-2-5. [Zn(H
2
O)
5
][Zn
2
(muia)
2
(H
2
O)
2
],
IIA

-
6
49
2-A-2-3. Infrared studies 53
2-A-2-4. UV-vis absorption studies 54
2-A-2-5. Thermogravimetric and ESI-MS studies 55
2-A-2-6. Solid-state fluorescence studies 57
2-A-3. Summary 59

Part B Self-Assembly of Ion-Pair Complexes: One-pot Crystallization
and Pseudosupramolecular Isomerism
60
2-B-1. Introduction 61
2-B-2. Results and discussion 63
2-B-2-1. Synthesis 63
2-B-2-2. Description of crystal structures 63
2-B-2-2-1. [Co(H
2
O)
4
(CH
3
CN)
2
][Co(muia)(H
2
O)
2
]
2

,
IIB
-
1
63
2-B-2-2-2. [Co(H
2
O)
6
][Co
2
(muia)
2
(H
2
O)
2
]
×
2CH
3
CN, IIB-2
66
2-B-2-2-3. [{Co(H
2
O)
4
}{Co
2
(muia)

2
(H
2
O)
2
}]
×
11H
2
O, IIB-3
69
2-B-2-3. Infrared studies 73

V
2-B-2-4. UV-vis absorption studies 74
2-B-2-5. Thermogravimetric and ESI-MS studies 75
2-B-3. Summary 76

Part C Experimental section
78
2-C-1. Synthesis of complexes 78
2-C-2. X-ray crystallography 81

Chapter 3 Complexes of N-(7-hydroxy-4-methyl-8-coumarinyl)-amino
acid as Novel Functional Crystalline and Gel Materials
82
Preface to Chapter 3 83

Part A Metal Complexes of Coumarin Derivatized Amino Acid: Towards
Crystalline Materials

84
3-A-1. Introduction 85
3-A-2. Results and discussion 86
3-A-2-1. Synthesis 86
3-A-2-2. Description of crystal structures 86
3-A-2-2-1. H
2
mugly, III-a 86
3-A-2-2-2. H
2
muala,
III
-
b
90
3-A-2-2-3. [Cu
2
(muala)
2
(H
2
O)
2
]·2H
2
O, IIIA-2 92
3-A-2-2-4. [Ni
7
(mugly)
6

(OH)
6
Na
6
(H
2
O)
6
]
×
20H
2
O, IIIA-4
95
3-A-2-2-5.[Ni
4
(mugly)
4
(H
2
O)
2
(
m
2
-CH
3
COO)K
2
(H

2
O)
4
(EtOH)]
×
-
H
2
O×EtOH, IIIA-7
98
3-A-2-2-6. [Ni
5
(muala)
2
(
m
2
-CH
3
COO)
4
(OH)
2
(H
2
O)
4
]
×
2.75H

2
O-

×0.5DMF, IIIA-8
101
3-A-2-2-7. [Zn(muala)(H
2
O)]
×
0.5H
2
O, IIIA-10
104
3-A-2-2-8. [Zn(Hmuser)(H
2
O)]
×
0.5H
2
O, IIIA-11
108
3-A-2-3. Infrared studies 109
3-A-2-4. UV-vis absorption studies 111

VI
3-A-2-5. Fluorescence studies 115
3-A-2-6. Thermogravimetric and ESI-MS studies 117
3-A-3. Summary 121

Part B Hydrogelation of Fluorescent Zinc(II) Coordination Polymer:

Synthesis, Photophysical and Gelation Properties
123
3-B-1. Introduction 124
3-B-2. Results and Discussion 125
3-B-2-1. Synthesis and properties of hydrogel 125
3-B-2-2. Microscopic morphological studies 126
3-B-2-3. UV-vis absorption studies 127
3-B-2-4. Fluorescence studies 131
3-B-2-5. Rheological studies 136
3-B-3. Summary 141

Part C Gelation-induced Fluorescence Enhancement of Amorphous
Magnesium(II) Coordination Polymeric Hydrogel
143
3-C-1. Introduction 144
3-C-2. Results and discussion 145
3-C-2-1. Synthesis and properties of hydrogel 145
3-C-2-2. Microscopic morphological studies 148
3-C-2-3. UV-vis absorption studies 150
3-C-2-4. Fluorescence studies 153
3-C-2-5. Rheological studies 158
3-C-3. Summary 164

Part D Experimental Section
166
3-D-1. Synthesis of ligands 166
3-D-2. Synthesis of complexes 167
3-D-3. Synthesis of hydrogels 174
3-D-4. X-ray crystallography 175

VII
Chapter 4 Coordination Polymers of Copper(II) Complexes of Reduced
Schiff Base Ligands, N-(2-pyridylmethyl)-amino acids: Synthesis,
Structures and Characterization
176
4-1. Introduction 177
4-2. Results and Discussion 178
4-2-1. Synthesis 178
4-2-2. Description of crystal structures 180
4-2-2-1. [Cu(Pbals)(H
2
O)
2
]
×
ClO
4
×
H
2
O, IV-1
180
4-2-2-2. [Cu(Pbal)(ClO
4
)(H
2
O)],
IV
-
2

183
4-2-2-3. [Cu
2
(Paes)
2
(ClO
4
)
2
]
×
2H
2
O, IV-3
185
4-2-2-4. [Cu(Pae)(DMF)(H
2
O)]
×
ClO
4
IV-5a
188
4-2-2-5. [Cu(Pae)
2
]
×
2H
2
O, IV-6

190
4-2-2-6. [Cu(HPser)(CH
3
COO)],
IV
-
8
192
4-2-3. Infrared studies 195
4-2-4. UV-vis absorption studies 196
4-2-5. Thermogravimetric and ESI-MS studies 198
4-3. Summary 200
4-4. Experimental 202
4-4-1. Synthesis of ligands 202
4-4-2. Synthesis of complexes 204
4-4-3. X-ray crystallography 207
Chapter 5 Conclusion and Future Work
208
5-1. Summary of the present work 208
5-2. Suggestions for future work 212
References 214
Appendix 228
A1. Chemicals and Physicochemical Methods 228
A2. Crystallographic data and structure refinement details 232
A3. Copyright permission 237
A4. Typical spectroscopic data of compounds 238
A5. Curriculum vitae 244

VIII
Abbreviations

1D one dimensional
2D two dimensional
3D three dimensional
2,2’-bpy 2,2’-bipyridine
4,4’-bpy 4,4’-bipyridine
Anal. Calcd. analysis calculated
CP gels coordination polymeric gels
d doublet
Decomp. decomposition
DMF dimethylformamide
DNA deoxyribonucleic acid
dt doublet of triplet
EDTA ethylenediaminetetraacetic acid
e.s.d estimated standard deviation (standard uncertainty parameter)
ESI-MS electrospray ionization mass spectroscopy
EtOH ethanol
Et
2
O diethyl ether
fac facial
FESEM field emission scanning electron microscopy
h hour
H
2
muala N-(7-hydroxy-4-methyl-8-coumarinyl)-L-alanine
H
2
mugly N-(7-hydroxy-4-methyl-8-coumarinyl)-glycine
H

3
muia 4-methylumbelliferone-8-methyleneiminodiacetic acid / Calcein Blue
H
3
muser N-(7-hydroxy-4-methyl-8-coumarinyl)-L-serine
HPae N-2(-pyridylmethyl)-aminoethanesulfonic acid
HPaes N-(2-pyridylmethylene)-aminoethanesulfonic acid
HPala N-2(-pyridylmethyl)-L-alanine
HPbal N-2(-pyridylmethyl)-
b
-alanine
HPbals N-(2-pyridylmethylene)-
b
-alanine
H
2
Pglu N-(2-pyridylmethyl)-L-glutamic acid
HPgly N-(2-pyridylmethyl)-glycine
HPhis N-(2-pyridylmethyl)-L-histidine
H
2
Pser N-(2-pyridylmethyl)-L-serine
H
2
Sae N-(2-hydroxybenzyl)-aminoethanesulfonicacid
H
2
Sala N-(2-hydroxybenzyl)-L-alanine
H
2

Sbal N-(2-hydroxybenzyl)-
b
-alanine
H
2
ClSala N-(2-hydroxy-5-chlorobenzyl)-L-alanine
H
2
MeSala N-(2-hydroxy-5-methylbenzyl)-L-alanine
H
2
Scp11 N-(2-hydroxybenzyl)-1-aminocyclopentatecarboxylic acid
H
2
Sgly N-(2-hydroxybenzyl)-glycine
H
3
Sglu N-(2-hydroxybenzyl)-L-glutamic acid
H
2
Shis N-(2-hydroxybenzyl)-L-histidine
H
2
Sval N-(2-hydroxybenzyl)-L-valine

IX
Hz hertz
IR infra red
LMCT ligand to metal charge transfer
m multiplet

max maximum
M metal
Me methyl
mer meridional
MeOH methanol
MLCT metal to ligand charge transfer
nm nanometer
mp melting point
NMR nuclear magnetic resonance
phen 1,10-phenanthroline
ppm parts per million
s singlet
SAFIN self-assembled fibrillar networks
t triplet
temp temperature
TEM Transmission electron microscopy
TG thermogravimetric analysis
UV ultraviolet
UV-vis ultraviolet-visible
wt % weight percentage
XRPD X-ray powder diffraction

X
Summary

In this study, three different types of multidentate amino acid ligands have been
employed to investigate their coordination behavior with divalent transition and main
group metal ions. They are 4-methylumbelliferone-8-methyleneiminodiacetic acid
(H
3

muia), N-(7-hydroxy-4-methyl-8-coumarinyl)-amino acid (amino acid = glycine
(H
2
mugly), alanine (H
2
muala), serine (H
3
muser)) and N-(2-pyridylmethyl)-amino acid
(amino acid =
b
-alanine (HPbal), amino ethane sulfonic acid (HPae), L-serine (H
2
Pser),
L-glutamic acid (H
2
Pglu)).
The introductory chapter gives literature background and brief summary on the
metal complexes of reduced Schiff base ligands derived from aldehydes and various
amino acids, and supramolecular gels relevant to the thesis. In Chapter 2, a series of
metal complexes containing the 4-methylumbelliferone-8-methyleneiminodiacetic acid
(Calcein Blue) have been presented. In Part A, the structural diversity of Calcein Blue
complexes as monomeric, ion-pair and coordination polymer is presented. The solid-state
fluorescence properties of these complexes have been studied. In Part B, self-assembly of
Co(II) muia as ion-pair complexes has been exemplified. Hydrogen bonding interactions
are dominant along with p-p interactions in the solid-state structures.
Driven by these results, the coordination chemistry of coumarin derivatized
amino acid ligands is further explored in Chapter 3. In Part A, the synthesis and
characterization of Cu(II), Ni(II), Zn(II), Mg(II) and Ca(II) complexes of N-(7-hydroxy-
4-methyl-8-coumarinyl)-amino acid have been described. Interestingly, variation the
metal ions and solvents have resulted in the isolation of crystalline and gel materials. The

XI
crystalline solids including Cu(II), Ni(II) and Zn(II) complexes have been structurally
characterized as coordination polymers and metal clusters. The Mg(II) and Ca(II)
complexes are shown to be amorphous in nature. It is noteworthy that Zn(II) complex of
H
2
mugly and Mg(II) complex of H
2
muala have been discovered to gelate water upon
formation of coordination polymer, without the involvement of long chain hydrophobic
groups. Hence, Part B and C are devoted to discuss these two hydrogels respectively in
detail. Comprehensive photophysical and rheological studies have been performed to
study these hydrogels. The results indicate that the hydrogels exhibit remarkable
fluorescence properties and weak gel behavior. Furthermore, in the absence of long chain
appended groups, coordination polymers have been demonstrated to be able to achieve
gelation. Coordination polymeric gels have provided new insight of properties,
functionality and application compared to their highly crystalline counterpart.
In Chapter 4, the synthesis and characterization of Cu(II) complexes of N-(2-
pyridylmethyl)-amino acid ligands have been discussed. The role of carboxylate and
sulfonate functional group in Cu(II) coordination have been evaluated based on Schiff
base and its reduced form with
b
-alanine and amino ethane sulfonic acid. Furthermore,
reduced Schiff base ligands with additional functional groups in the amino acid side
chain, namely L-serine and L-glutamic acid have been utilized in the complexation with
Cu(II). These Cu(II) complexes have been demonstrated as one-dimensional coordination
polymers with diverse hydrogen bonding motifs.
In summary, this thesis demonstrates the utilization of weak intermolecular
interactions such as hydrogen bonding and p-p interactions in the self-assembly of

crystalline and amorphous gel materials.

XII
List of Compounds Synthesized

Code Name and Formula Structure
H
3
muia 4-methylumbelliferone-8-
methyleneiminodiacetic acid
(H
3
muia) or Calcein Blue
O
Me
OHO
N
OH
O
O
HO

IIA-1
[Cu(Hmuia)(H
2
O)]
×
CH
3
OH

×

2H
2
O*
O
Me
O
N
O
O
Cu
OH
2
O
O
O

IIA-2
[Ni(Hmuia)(H
2
O)
2
]
×
2H
2
O*
O
Me

O
N
Ni
OH
2
H
O
O
O
O
OH
2
O

IIA-3
[Mn(H
2
O)
6
][Mn
2
(muia)
2
-
(H
2
O)
2
]× 2CH
3

CN*
OH
2
Mn
OH
2
OH
2
OH
2
H
2
O
H
2
O
Mn
OH
2
O
O
O
Me
O
N
O
O
O
Mn
H

2
O
O
O
O
Me
O
N
O
O
O
2+
2-

IIA-4
[Mg(H
2
O)
6
][Mg
2
(muia)
2
-
(H
2
O)
2
]×2CH
3

CN*
Mg
OH
2
O
O
O
Me
O
N
O
O
O
Mg
H
2
O
O
O
O
Me
O
N
O
O
O
OH
2
Mg
OH

2
OH
2
OH
2
H
2
O
H
2
O
2-
2+

IIA-5
[Mn(H
2
O)
4.5
(CH
3
OH)
1.5
]-
[{Mn
2
(muia)
2
}{Mn
2

(muia)
2
-
(H
2
O)
2
}]×5H
2
O*
OH
2
Mn
OH
2
H
O
O
H
H
2
O
H
2
O
Mn
O
O
O
MeO

N
O
O
O
Mn
O
O
O
Me O
N
O
O
O
OH
2
OH
2
Mn
N
O
O
O
O
O
Me
O
O
Mn
N
O

O
O
O
O
Me
O
O
Mn
Mn
Me
Me
2-
2+


XIII
IIA-6
[Zn(H
2
O)
5
][Zn
2
(muia)
2
(H
2
O)
2
]

*
Zn
OH
2
O
O
O
Me
O
N
O
O
O
Zn
H
2
O
O
O
O
Me
O
N
O
O
O
H
2
O Zn
OH

2
OH
2
OH
2
OH
2
2+
2-

IIA-7
[Ca(H
2
O)
6
][Ca
2
(muia)
2
(H
2
O)
2
]
×2H
2
O
Ca
OH
2

O
O
O
Me
O
N
O
O
O
Ca
H
2
O
O
O
O
Me
O
N
O
O
O
OH
2
Ca
OH
2
OH
2
OH

2
H
2
O
H
2
O
2-
2+

IIA-8
[Al
2
(muia)
2
(H
2
O)
2
]
×
CH
3
CN
×
-
4H
2
O
Al

OH
2
O
O
O
Me
O
N
O
O
O
Al
H
2
O
O
O
O
Me
O
N
O
O
O

IIB-1
[Co(H
2
O)
4

(CH
3
CN)
2
]-
[Co(muia)(H
2
O)
2
]
2
*
O
Me
O
N
Co
OH
2
O
O
O
O
H
2
O
O
O
Me
O

N
Co
OH
2
O
O
O
O
H
2
O
O
N
Co
N
OH
2
OH
2
H
2
O
H
2
O
CCH
3
CCH
3
2+

-
-

IIB-2
[Co(H
2
O)
6
][Co
2
(muia)
2
(H
2
O)
2
]
-×2CH
3
CN*
Co
OH
2
O
O
O
Me
O
N
O

O
O
Co
H
2
O
O
O
O
Me
O
N
O
O
O
OH
2
Co
OH
2
OH
2
OH
2
H
2
O
H
2
O

2-
2+

IIB-3
[{Co(H
2
O)
4
}{Co
2
(muia)
2
-
(H
2
O)
2
}]×11H
2
O*
Co
OH
2
O
O
O
Me
O
N
O

O
O
Co
H
2
O
O
O
O
Me
O
N
O
O
O
Co
O
OH
2
OH
2
H
2
O
H
2
O
Co

XIV
H
2
mugly
III-a
N-(7-hydroxy-4-methyl-8-
coumarinyl)-glycine*
O
Me
OHO
HN
O
HO

H
2
muala
III-b
N-(7-hydroxy-4-methyl-8-
coumarinyl)-L-alanine*
O
Me
OHO
HN
Me
O
HO

H
3

muser
III-c
N-(7-hydroxy-4-methyl-8-
coumarinyl)-L-serine
O
Me
OHO
HN
O
HO OH

IIIA-1
[Cu
2
(mugly)
2
(H
2
O)
2
]
×
5H
2
O
×
-
0.5DMF
Cu
O

O
O
Me
O
NH
O
Cu
O
O
O
O
Me
O
NH
O
H
2
O
Cu
OH
2

IIIA-2
[Cu
2
(muala)
2
(H
2
O)

2
]
×
2H
2
O*
Cu
O
O
O
Me
O
NH
O
Cu
O
O
O
O
Me
O
NH
O
H
2
O
Cu
OH
2
Me

Me

XV

IIIA-3
[Cu
2
(Hmuser)
2
(H
2
O)
2
]
×
5H
2
O
Cu
O
O
O
Me
O
NH
O
Cu
O
O
O

O
Me
O
NH
O
H
2
O
Cu
OH
2
HO
OH

IIIA-4
[Ni
7
(mugly)
6
(OH)
6
Na
6
(H
2
O)
6
]
·20H
2

O*
NH
Ni
OH
O
OHO
O
Ni
OH
O
Ni
OH
OH
OH
Ni
O
O
Ni
Ni
O
O
NH
O
O
Me
O
O
O
Me
O

NHO
O
Me
O
NH
O
O
O
Me
O
O
O
Me
O
NH O
Ni
O
NH
O
O
Me
O
O
Na OH
2
Na
H
2
O
Na

OH
2
NaH
2
O
Na
H
2
O
Na
OH
2
O
OH
2
O
H
2
O
O
OH
2
H
2
O
OH
2
O
OH
2

O
O

IIIA-5
[Ni
7
(muala)
6
(OH)
6
Na
6
(H
2
O)
6
]
·18H
2
O
NH
Ni
OH
O
OHO
O
Ni
OH
O
Ni

OH
OH
OH
Ni
O
O
Ni
Ni
O
O
NH
O
O
Me
O
O
O
Me
O
NHO
O
Me
O
NH
O
O
O
Me
O
O

O
Me
O
NH O
Ni
O
NH
O
O
Me
O
O
Me
Me
Me
Me
Me
Me
Na OH
2
Na
OH
2
Na
H
2
O
NaH
2
O

Na
H
2
O
Na
OH
2
O
OH
2
H
2
O
O
H
2
O
O
H
2
O
O
OH
2
O
OH
2
O

XVI
IIIA-6
[Ni
7
(Hmuser)
6
(OH)
6
Na
6
-
(H
2
O)
6
] ×16H
2
O
NH
Ni
OH
O
OHO
O
Ni
OH
O
Ni
OH
OH

OH
Ni
O
O
Ni
Ni
O
O
NH
O
O
Me
O
O
O
Me
O
NHO
O
Me
O
NH
O
O
O
Me
O
O
O
Me

O
NH O
Ni
O
NH
O
O
Me
O
O
HO
HO
HO
OH
OH
OH
Na
Na
Na
Na
Na
Na
OH
2
H
2
O
H
2
O

H
2
O
OH
2
OH
2
O
O
H
2
O
H
2
O
O
H
2
O
O
OH
2
O
OH
2
O
OH
2

IIIA-7

[{Ni
4
(mugly)
4
(H
2
O)
2
(
m
2
-
CH
3
COO)}{K
2
(H
2
O)
4
(EtOH)
2
}]×H
2
O×EtOH*
O
Me
O
O
Me

O
N
H
N
i
O
O
H
2
O
O
O
O
K
H
2
O
O
OH
2
H
2
O
O
Ni
N
H
2
O
O

O
O
Me
O
O
Me
O
H
N
N
i
O
O
OH
2
O
O
O
K
OH
2
O
H
2
O
OH
2
O
Ni
N

OH
2
O
O

IIIA-8
[Ni
5
(muala)
2
(
m
2
-CH
3
COO)
4
-
(m
3
-OH)
2
(H
2
O)
4
]×2.75H
2
O-
×0.5DMF*

IIIA-9
and
IIIB-1
[Zn(mugly)(H
2
O)]·0.5H
2
O
O
O
Me NH
O
Zn
O
OH
2
O
O
Zn


XVII
IIIA-10
[Zn(muala)(H
2
O)]·0.5H
2
O*
O

O
Me NH
O
Zn
O
OH
2
O
O
Zn
Me

IIIA-11
[Zn(Hmuser)(H
2
O)]·0.5H
2
O*
O
O
Me NH
O
Zn
O
OH
2
O
O
Zn
OH

IIIA-12
[Mg(mugly)(H
2
O)
2
]·0.5H
2
O
O
O
Me N
H
O
Mg
O
O
O
H
2
O
OH
2
Mg

IIIA-13
or
IIIC-1
[Mg(muala)(H
2

O)(MeOH)
0.5
]
O
O
Me N
H
O
Mg
O
O
O
H
2
O
OH
2
Mg
Me

IIIA-14
[Mg(Hmuser)(H
2
O)
2
]·1.5H
2
O
O
O

Me N
H
O
Mg
O
O
O
H
2
O
OH
2
Mg
OH

IIIA-15
[Ca(mugly)(MeOH)]
×
0.5DMF
O
O
Me N
H
O
Ca
O
O
O
H
2

O
OH
2
Ca

XVIII

IIIA-16
[Ca(muala)(H
2
O)
2
]·0.5H
2
O
O
O
Me N
H
O
Ca
O
O
O
H
2
O
OH
2
Ca

Me

IIIA-17
[Ca(Hmuser)(H
2
O)
2
]
O
O
Me N
H
O
Ca
O
O
O
H
2
O
OH
2
Ca
OH

HPbals
N-(2-pyridylmethylene)-
b
-
alanine

N
N OH
O

HPbal
N-(2-pyridylmethyl)-
b
-alanine
N
N
H
OH
O

HPaes N-(2-pyridylmethylene)-amino
ethane sulfonic acid
N
N
S
O
O
OH

HPae N-(2-pyridylmethyl)-amino
ethane sulfonic acid
N
N
H
S
O

O
OH

H
2
Pser N-(2-pyridylmethyl)-L-serine
N
N
H
O
OH
OH


XIX
H
2
Pglu N-(2-pyridylmethyl)-L-
glutamic acid
N
N
H
O
OH
OH
O

IV-1
[Cu(Pbals)(H
2

O)
2
]ClO
4
×
H
2
O*
N
N
ClO
4
-
Cu
O
OO
OH
2
H
2
O
Cu
+

IV-2
[Cu(Pbal)(ClO
4
)(H
2
O)]*

N
NH
Cu
O
OO Cu
O
Cl
O
OH
2
O
O

IV-3
[Cu
2
(Paes)
2
(ClO
4
)
2
]
×
2H
2
O*
N
N
S

O
O
O
Cu
H
2
O
O
Cl
O
O
O
N
N
S
O
O
O
Cu
OH
2
O
Cl
O
O
O

IV-4
[Cu(Paes)
2

]
×
9H
2
O
N
N
S
O
O
O
Cu
N
N
S
O
O
O

IV-5
[Cu(Pae)(H
2
O)]ClO
4
×
H
2
O
N
NH

S
O
O
Cu
O
OH
2
O
Cu
ClO
4
-
+

IV-5a
[Cu(Pae)(DMF)(H
2
O)]
×
ClO
4
*
N
NH
S
O
O
Cu
DMF
O

OH
2
O
Cu
ClO
4
-
+

XX

IV-6
[Cu(Pae)
2
]
×
2H
2
O*
N
NH
S
O
O
O
Cu
N
NH
S
O

O
O

IV-7
[Cu(HPser)(H
2
O)]ClO
4
×
3H
2
O
N
NH
OH
O
O
Cu
OH
2
O
O
Cu
ClO
4
-
+

IV-8
[Cu(HPser)(CH

3
COO)]*
N
N
OH
O
O
Cu
O
O
O
Cu

IV-9
[Cu(pglu)]ClO
4
×
H
2
O
N
NH
O
O
Cu
O
O
Cu
O
O

ClO
4
-
+

* Crystal structure determined

XXI
List of Figures
Chapter 1
Figure 1-1.
Representative supramolecular synthons.

4
Figure 1-2.
Principal orientations of aromatic-aromatic interactions.

5
Figure 1-3.
Molecular structure of [Cu
8
(Shis)
8
Py
10
]
×
Py
×
3MeOH

×
(C
2
H
5
)
2
O
showing the trapped pyridine molecules
8
Figure 1-4.
Reduced Schiff base ligands of N-(2-hydroxybenzyl)-amino acids. 10
Figure 1-5.
(a) Interactions between the carboxyl group and the phenyl ring;
(b) C=O
¼
p interaction between the caboxylate CO group and the
phenyl ring.
11
Figure 1-6.
Schematic diagram of supramolecular isomers 11
Figure 1-7.

Hydrogen-bonded helical water chain inside the staircase 1D
polymer
13
Figure 1-8.
Ligands derived from pyridine-2-aldehyde and various amino
acids
15

Figure 1-9.


pH dependent interconversion of Cu(II) complexes of HPhis 16
Figure 1-10.
Metallocrown structures of Cu(II) complexes of (a) HPgly; (b)
HPala
17
Figure 1-11.
Various 1D polymers derived from HPgly and HPala ligands

18
Figure 1-12.
Schematic representation of aggregation modes 21
Figure 1-13.
Schematic representation of the formation of metallo-
supramolecular polymeric aggregates
24
Figure 1-14.
Luminescent Pt(II) quinolinol derivative gel: (a) luminescence
spectra; (b) photograph under UV light; (c) confocal laser
scanning image
26
Figure 1-15.
Schematic representation of the self-assembly process of the CP
gels
28
Figure 1-16.
Structure of Calcein Blue ligand

29
Figure 1-17.
Coumarin derivatized amino acid, N-(7-hydroxy-4-methyl-8-
coumarinyl)-amino acid ligand structures
30
Figure 1-18.
N-(2-pyridylmethyl)-amino acid ligands

31

Chapter 2
Figure 2-1.
A perspective view of
IIA
-
1
showing the (H
2
O)
3
cluster

38
Figure 2-2.

A portion of the 2D structure present in the crystal structure of
IIA-1 viewed from c-axis. The C-H hydrogen atoms are not
shown for clarity.
39
Figure 2-3.

A perspective view of
IIA
-
2
. Solvent molecules and C-H
hydrogen atoms are omitted for clarity.
40
Figure 2-4.

(a) Hydrogen-bonded network of
IIA
-
2
; (b) Packing diagram of
IIA-2 showing the hydrogen bonding and p-p interactions.
41
Figure 2-5.

Perspective view of ion-pair complex
IIA
-
3
. Solvent molecules
and C-H hydrogen atoms are omitted for clarity. The atoms with
the extension ‘A’ are related by the symmetry -x+1, -y+1, -z+1.
43
Figure 2-6.
(a) Perspective view of the ion pair complex
IIA

-
3
showing the 45

XXII



interactions between cations and anions in bc-plane; (b)
interactions between anions only. Solvent molecules and C-H
hydrogen atoms are omitted for clarity.
Figure 2-7.

(a) A perspective view of asymmetric unit of the anion in
IIA
-
5
.
The atoms with the extension ‘A’ are related by the symmetry -
x+1, -y+1, -z+1; (b) The schematic representation of the 1D
polymeric anion in IIA-5. The Mn(II) cation and solvent
molecules are omitted for clarity.
47
Figure 2-8.

Packing diagram of
IIA
-
5
showing hydrogen bonding interactions

between anionic polymer and Mn(II) cations; (b) Placement of
Mn(II) cations within the anionic polymeric strands. All C-H
hydrogen atoms and solvent molecules are omitted for clarity.
48
Figure 2-9.


A perspective view of
IIA
-
6
with disordered pentaaqua Zn(II)
cation. The atoms with the extension ‘A’ are related by the
symmetry -x+1, y, -z+½.
50
Figure 2-10.

(a) A packing diagram of anionic

IIA
-
6
down from c-axis
showing honeycomb-like cavity; (b) Perspective view of IIA-6
showing cations in the honeycomb-like cavity with space filling
model; (c) Hydrogen bonding interactions between anions; (d) and
(e) Intermolecular interactions between anions and cations in ab-
plane.
52
Figure 2-11.

Solid-state fluorescence spectra for complexes
IIA
-
1
to
IIA
-
8
upon excitation at l = 350 nm.
58
Figure 2-12.

A perspective view of
IIB
-
1
. The atoms with the extension ‘A’ are
related by the symmetry -x+1, -y+1, -z+1.
64
Figure 2-13.

(a) A perspective view of the hydrogen-bonded network of
IIB
-
1

viewed from Z-direction; (b) Hydrogen-bonding interaction
between cation and anion; (c) A perspective view of hydrogen
bonding interactions between the anions with the labeling scheme.

All C-H hydrogen atoms are omitted for clarity.
65
Figure 2-14.

A perspective view of the ion-pair complex of
IIB
-
2
. All
hydrogen atoms and solvent molecules are omitted for clarity. The
atoms with the extension ‘A’ are related by the symmetry -x+1, -
y+1, -z+1.
67
Figure 2-15.



(a) A perspective view of the alternating arrangement of the ion-
pair in IIB-2; (b) Hydrogen bonding and p-p interactions between
the anions. The C-H hydrogen atoms and solvent molecules are
omitted for clarity.
68
Figure 2-16.

A perspective view in the repeating unit of the 1D polymer
IIB
-
3

by ion pairing. The atoms with the extension ‘A’ and ‘B’ are

related by the symmetry -x+1, -y+1, -z+1 and -x+1, -y+1, -z
respectively.
70
Figure 2-17.

(a) A view along the a-axis showing a portion of the 2D
hydrogen-bonded structure in IIB-3; (b) A perspective view of
hexameric water cluster encapsulated in the 2D framework. All
hydrogen atoms are omitted for clarity.
72
XXIII

Figure 2-18.
Self-assembly of Co(II) muia complexes 77


Chapter 3
Figure 3-1.
A perspective view of
III
-
a

87
Figure 3-2.
A portion of III-a showing the
p
-
p
interactions. Green atoms

represent the centroid of phenyl ring.
88
Figure 3-3.

(a) A portion of 3D hydrogen-bonded network of
III
-
a
; (b)
Packing of III-a viewed down c-axis
89
Figure 3-4.
A perspective view of
III
-
b

91
Figure 3-5.
Hydrogen bonded 2D sheet structure of
III
-
b
in ab-plane

91
Figure 3-6.

A perspective view of
IIIA

-
2
. All C-H hydrogen atoms and
solvent molecules are omitted for clarity.
93
Figure 3-7.

(a) Helical polymeric chain of
IIIA
-
2
; (b) A portion of 1D
coordination polymeric chain in IIIA-2; (c) Schematic
representation of 1D coordination polymer of IIIA-2; (d) Packing
diagram of IIIA-2 showing 2D hydrogen bonding interactions
between 1D chains.
94
Figure 3-8.
A perspective view of metallocrown ring of
IIIA
-
4

96
Figure 3-9.

(a) Heptanickel cluster structure of
IIIA
-
4

; (b) Simplified diagram
of Ni
7
O
12
cluster showing five types of Ni-O interactions.
97
Figure 3-10.

(a) A ball-and-stick diagram of
IIIA
-
7
. All C-H hydrogen atoms
and solvent molecules are omitted for clarity. The atoms with the
extension ‘A’ are related by the symmetry –x+1, -y, -z+1; (b)
Schematic representation of heterobimetallic cage of IIIA-7
showing the dimensions. Green atoms represent the center of
Ni
2
O
2
ring; yellow atoms represent the potassium cation; grey
bonds represent coumarin rings; red bonds represent metal-oxygen
bond.
99
Figure 3-11.
A perspective view of
IIIA
-

8
showing a pentanickel cluster. The
atoms with the extension ‘A’ are related by the symmetry –x+2, y,
-z+½.
102

Figure 3-12.

Molecular structure of
IIIA
-
8
showing (a) in-depth cavity; (b)
molecular basket shape.
103

Figure 3-13.
(a) A perspective view of
IIIA
-
10
. The atoms with the extension
‘A’ are related by the symmetry x-y+1, -y+1, -z+⅓; (b) A portion
of the 1D coordination polymer of IIIA-10. All the hydrogen
atoms are omitted for clarity.
105

Figure 3-14.

(a) Packing of

IIIA
-
10
viewed from the c-axis; (b) Packing of
IIIA-10 viewed down the b-axis. All the hydrogen atoms are
omitted for clarity.
106

Figure 3-15.

X-ray powder pattern of the [i] simulated XRPD; [ii] dried
powder; [iii] freeze dried IIIA-10; [iv] dried powder IIIA-9.
107

Figure 3-16.
Perspective view of the repeating unit in
IIIA
-
11

108

Figure 3-17.

Packing of
I
IIA
-
11
viewed from b-axis. All C-H hydrogen atoms

are omitted.
109

Figure 3-18.
UV-vis absorption spectra of ligands
III
-
a
to
III
-
c
([
III
-
a
] = 1.01 112


XXIV

x 10
-
4
M, [
III
-
b
] = 1.04 x 10
-

4
M and [
III
-
c
] = 1.04 x 10
-
4
M) in
(a) aqueous solution; (b-d) buffer solutions at various pH.
Figure 3-19.

UV-vis absorption spectra of ligand
III
-
a
to
III
-
c
([
III
-
a
] = 1.01 x
10
-4
M, [III-b] = 1.04 x 10
-4
M and [III-c] = 1.04 x 10

-4
M) in the
presence of one equivalent of Zn(II) in (a-c) aqueous solution; (d-
f) buffer solution at various pH.
114

Figure 3-20.

Fluorescence spectra of ligands
III
-
a
to
III
-
c
in (a) aqueous
solution; (b) solid-state
116

Figure 3-21.

(a) Fluorescence spectra of
III
-
a
to
III
-
c

in the presence of one
equivalent Zn(II) upon excitation at 350 nm; (b) Photograph of
ligand and complex solution under UV light.
116

Figure 3-22.
The photograph of ligand
III
-
a
(left) and hydrogel
IIIB
-
1
(right).

125

Figure 3-23.


FESEM image of freeze dried
IIIB
-
1

126

Figure 3-24.

(a) UV-vis spectral traces of
III
-
a
upon Zn(II) binding in H
2
O in
the presence of two equivalents of LiOH ([III-a] = 9.12 x 10
-5
M);
(b) Job’s plot for 1:1 binding of III-a with Zn(II) in H
2
O, with the
absorbance at 360 nm monitored (c
host
= [III-a]/[III-a]+[Zn
2+
] and
DA is the change in absorbance at 360 nm).
128

Figure 3-25.

(a) UV-vis absorption spectra of
III
-
a
in H
2
O and hydrogel

IIIB
-
1

([1] and [IIIB-1] = 25 mM); (b) UV-vis absorption spectra of
hydrogel IIIB-1 and its corresponding sol state in acidic medium
([IIIB-1] = 25 mM)
128

Figure 3-26.

(a) UV-vis absorption spectra of
III
-
a

in the presence of one
equivalent of Zn(II) at various pH in buffer solutions; (b) UV-vis
absorption spectra of hydrogel IIIB-1 at various temperatures; (c)
UV-vis absorption spectra of III-a + Co(II), III-a + Ni(II) in H
2
O,
and hydrogel IIIB-1 ([III-a] and [IIIB-1] = 25 mM).
130

Figure 3-27.

Emission spectra of
III
-

a
to
III
-
c
(25 mM) upon addition of one
equivalent of Zn(II) in H
2
O upon excitation at l = 350 nm.
131

Figure 3-28.
(a) Emission spectra of
III
-
a
in H
2
O and hydrogel
III
B
-
1
([
III
-
a
]
and [IIIB-1] = 25 mM) upon excitation at l = 340 nm where the
absorbance for all samples are the same; (b) photograph of the

hydrogel IIIB-1 under UV light; (c) fluorescence micrograph of
freeze dried IIIB-1.
132

Figure 3-29.

Emission spectra of
III
-
a
upon addition of Zn(II) in H
2
O in the
presence of two equivalents LiOH upon excitation at l = 352 nm.
133

Figure 3-30.

Emission spectra of (a) hydrogel
IIIB
-
1
and Co(II) +
III
-
a
upon
excitation at 318 nm, and (b) hydrogel IIIB-1 and Ni(II) + III-a
upon excitation at 310 nm.
134

Figure 3-31.

Emission spectra of hydrogel
IIIB
-
1
before and after pH response
upon excitation at l = 340 nm.
135

Figure 3-32.

The fluorescence decay profiles of
III
-
a
and hydrogel
IIIB
-
1
. The
samples were excited at 400 nm and monitored at 450 nm.
135

Figure 3-33.

Dynamic oscillatory strain sweep for hydrogel
IIIB
-

1
at frequency
of 1 rad s
-1
and 25°C.
136

Figure 3-34.
Dynamic frequency sweep for hydrogel
IIIB
-
1
: (primary axis) G' 138