Polyphenylene dendrimers [Elektronische Ressource] : design and synthesis of monodisperse functional nanoparticles / vorgelegt von Stefan Bernhardt

Administrator

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2006
• Nombre de lectures: 7
• Langue: English
• Poids de l'ouvrage: 15 Mo

Extrait

Polyphenylene Dendrimers -
Design and Synthesis of Monodisperse
Functional Nanoparticles


Dissertation zur Erlangung des Grades
"Doktor der Wissenschaften"
am Fachbereich Chemie und Pharmazie
der Johannes Gutenberg-Universität in Mainz



vorgelegt von



Stefan Bernhardt
geb. in Hofheim a. Ts.



Mainz 2005































Dekan: Herr Prof. Dr. P. Langguth
1. Berichterstatter:
2. Berichterstatter:
Tag der mündlichen Prüfung: 26.06.2006
Die vorliegende Arbeit wurde in der Zeit von März 2002 bis März 2005 am Max-Planck-
Institut für Polymerforschung in Mainz unter Anleitung von Herrn Prof. Dr. K. Müllen
durchgeführt.



































Dedicated to my wife

















If we knew what we were doing it wouldn't be research.
Einstein, Albert
















Index of Abbreviations:

AFM atomic force microscopy
Anal. analysis
calcd. calculated
TBAF tetrabutylammoniumfluoride-hexahydrate
CD Cldeuterated methylenechloride 2 2
δ chemical shift / ppm
d doublet
8dTHF deuterated tetrahydrofuran
DEE diethylether
DMF dimethylformamide
DMSO ethylsulfoxide
eq. equivalent
EtOH ethanol
FD field desorption
G1, G2, G3, first-, second-, and third-dendrimer generation
GS ground state
h hours
J coupling constant / Hz
LE locally-excited state
m multiplett
m / g weight in gram
MALDI-TOF matrix-assisted laser desorption/ionization-time of flight
MCH methylcyclohexane
MeOH ethanol
MS ass spectrometry
n refractive index
NMR nuclear magnetic resonance
PE petroleum ether, low boiling
PMI perylene monoimide
PPh triphenylphosphine 3
ppm parts per million (chemical shift in NMR spectroscopy)
RT room temperature
s singulet
SM single molecule
T temperature / °K or °C
t triplet
TCSPC time-correlated single photon counting
TEA triethylamine
THF tetrahydrofuran
TIPS tri-iso-propylsilyl
TPA triphenylamine
UV ultraviolett
Ф fluorescence quantum yield flu
τ decay time of fluorescence flu
k and k forward and reverse electron transfer rate constants fwd rev
CS charge-separated state



Table of contents
1 INTRODUCTION................................................................................................. 1
1.1 Dendrimer Chemistry, a Short Overview............................................................................................. 1
1.1.1 Linear Building Blocks ........................................................................................................................ 3
1.1.2 Branched Building Blocks ................................................................................................................... 4
1.2 Polyphenylene Dendrimers............. 5
1.3 Synthesis of Polyphenylene Dendrimers..... 6
1.3.1 Palladium Catalysed Aryl-Aryl Coupling Reactions ........................................................................... 6
1.3.2 Diels-Alder Cycloaddition ................................................................................................................... 7
1.3.2.1 Divergent Synthesis.................................................................................................................... 8
1.3.2.2 Convergent Sy ................................................................................................................. 9
1.4 Diversification of Shape........................................................................................................................ 10
1.4.1 Core.................................................................................................................................................... 10
1.4.2 Branching Units ................................................................................................................................. 11
1.5 Shape Persistence.................................................................................................................................. 12
1.5.1 Solid-State NMR................ 12
1.5.2 PFM-AFM Measurements...... 13
1.5.3 SANS Experiments ............................................................................................................................ 13
1.6 Functionalization.................... 13
1.6.1 Postsynthetic .................................................................................................................. 14
1.6.2 Presynthetic........................................................................................................................................ 15
1.7 Nomenclature 15
1.8 Motivation ............................................................................................................................................. 16
1.9 References......................... 16
2 PYRENE AS CHROMOPHORE AND ELECTROPHORE - ENCAPSULATION
IN A RIGID POLYPHENYLENE SHELL .................................................................. 18
2.1 Introduction .......................................................................................................................................... 18
2.2 Synthesis of Dendronized Pyrenes....................................................................................................... 24
2.2.1 Synthesis of the Pyrene Core 1,3,6,8-Tetraethynyl-pyrene................................................................ 24
2.2.2 of First- to Fourth-Generation Dendronized Pyrenes......................................................... 24
2.2.3 Improving the Film Forming Ability ................................................................................................. 27
2.2.4 Dendronized Pyrenes with a Higher Symmetry................................................................................. 28
2.2.5 Modification of the Pyrene Core – Toward New Dendrimer Shapes................................................. 29
2.3 Characterization of the Cores and the According Dendrimers ........................................................ 32
2.3.1 Characterization of the Cores............................................................................................................. 32
2.3.2 Characterization of the Dendrimers...... 33
2.4 Visualization and Simulation............................................................................................................... 35
2.4.1 Crystal Structure of a First-Generation Dendrimer............................................................................ 35
2.4.2 Molecular Modeling........................................................................................................................... 36
2.5 Pyrene as Chromophore....................................................................................................................... 39
2.5.1 Absorption and Emission in Solution ................................................................................................ 39
2.5.2 Absond Emission in Solid-State ............................................................................................ 43
2.5.3 Fluorescence Quenching Experiments............................................................................................... 45
2.5.4 Temperature Dependent Fluorescence Spectroscopy......................................................................... 47
2.6 Pyrene as Electrophore ........................................................................................................................ 49
2.6.1 Reduction of Dendronized Pyrenes on a Potassium Mirror ............................................................... 49
2.6.2 Electrochemical Studies..................................................................................................................... 52
2.7 Organic Light-Emitting Diodes ........................................................................................................... 54
2.8 Conclusion ............................................................................................................................................. 56
2.9 References......................... 58
3 BENZOPHENONE FUNCTIONALIZED POLY-PHENYLENE DENDRIMERS –
FROM INSIDE TO OUTSIDE ................................................................................... 62
3.1 Introduction .......................................................................................................................................... 62
3.2 Multiple Benzophenones in the Dendrimer Backbone ........................................................