D Thermodynamic and optical properties of naphthalene, fluorene and fluorenone derivatives

Juliana Andreia Silva Alves Oliveira Doutoramento em Química 2016 Departamento de Química e Bioquímica

Faculdade de Ciências da Universidade do Porto

Orientador Manuel João dos Santos Monte

Professor Associado do Departamento de Química e Bioquímica

Faculdade de Ciências da Universidade do Porto

Co-orientador Maria das Dores Melo da Cruz Ribeiro da Silva

Professora Associada do Departamento de Química e Bioquímica

Faculdade de Ciências da Universidade do Porto



.0

.2

.4

.6

.8

.0 Liquid

Crystal

Vapor

FCUP

I

To Mom, Dad and B

II

FCUP

III

Abstract

This dissertation describes the thermodynamic and optical study of 16 fluorene

derivatives, 4 fluorenone derivatives and 3 naphthalene derivatives, some of which were

synthesized for this purpose.

Differential scanning calorimetry analysis was performed in order to detect transitions

between condensed phases and to determine their enthalpies and temperatures of

transition.

The crystalline vapor pressures of all the compounds studied were measured using

the Knudsen mass-loss effusion method and/or a static method based on capacitance

manometers. The latter method also allowed the measurement of the liquid vapor pressures

of some of the compounds, enabling phase diagram representations. Sublimation and

vaporization properties (standard molar enthalpy, entropy and Gibbs energy) were

determined from the vapor pressure dependency with temperature, and occasionally using

also Calvet microcalorimetry.

The standard molar enthalpies of formation in the crystalline phase, were derived from

the standard massic energy of combustion, at T = 298.15 K, measured by combustion

calorimetric techniques for some of the compounds studied. For these compounds, the

combination of the standard molar enthalpies of formation in the crystalline phase and the

standard molar enthalpies of sublimation yielded the standard molar enthalpies of formation,

in the gaseous phase. The determined results enabled the evaluation of the thermodynamic

stability of the compounds by means of the Gibbs energy of formation, in crystalline and

gaseous phases.

After convenient tests on a new apparatus, fluorescence spectroscopic

measurements were performed to determine the fluorescence quantum yield and emission

properties of the compounds studied.

Keywords: Fluorene derivatives; Fluorenone derivatives; Naphthalene derivatives; Vapor

pressure; Sublimation; Vaporization; Fusion; Combustion; Enthalpy; Entropy; Gibbs energy;

Fluorescence; Quantum yield; Volatility; Stability.

IV

Resumo

Nesta dissertação é descrito o estudo termodinâmico e ótico de 16 derivados do

fluoreno, 4 derivados da fluorenona e 3 derivados do naftaleno, alguns dos quais foram

sintetizados neste trabalho.

Calorimetria diferencial de varrimento foi realizada com os objetivos de detetar as

transições entre as fases condensadas e determinar as respetivas temperaturas e entalpias

molares de fusão padrão.

As pressões de vapor da fase cristalina de todos os compostos estudados foram

medidas utilizando o método de efusão de Knudsen e/ou um método estático baseado em

manómetros de capacitância. O método estático também permitiu a medição pressões de

vapor da fase líquida de alguns dos compostos, possibilitando a representação dos

respetivos diagramas de fase. As propriedades de sublimação e vaporização (entalpia,

entropia e energia de Gibbs molar padrão) foram determinados a partir da dependência da

pressão do vapor com a temperatura e, ocasionalmente, usando também microcalorimetria

Calvet.

As entalpias molares de formação padrão na fase cristalina, foram derivadas a partir

de energias mássicas de combustão padrão, a T = 298.15 K, determinadas por calorimetria

de combustão para alguns dos compostos estudados. Para estes compostos, a

combinação das respetivas entalpias molares de formação padrão na fase cristalina com

as entalpias molares de sublimação padrão permitiu o cálculo das entalpias molares de

formação padrão, na fase gasosa. Estes resultados permitiram a avaliação da estabilidade

termodinâmica dos compostos por meio da energia de Gibbs de formação, das fases

cristalinas e gasosas.

Após testes convenientes a um novo aparelho, as propriedades de emissão dos

compostos estudados, incluindo o rendimento quântico de fluorescência, foram

determinadas por espectroscopia de fluorescência.

Palavras-chave: Derivados do fluoreno; Derivados da fluorenona; Derivados do naftaleno;

Pressão de vapor; Sublimação; Vaporização; Fusão; Combustão; Entalpia; Entropia;

Energia de Gibbs; Fluorescência; Rendimento quântico; Volatilidade; Estabilidade.

FCUP

V

Acknowledgments

I’d like to express my deepest gratitude,

To Professor Manuel João Monte, for the guidance throughout the years, for the

fruitful discussions and incentive, and for challenging me daily to develop the rational

thinking essential to a good scientist, which greatly contributed to the realization of this work.

To Professor Maria da Dores Ribeiro da Silva, for the support and availability, for the

transmitted knowledge and the constant encouragement.

To the late Professor Manuel Ribeiro da Silva, for always teaching me something new,

for all the given opportunities that lead to this point and for all they may lead to in the future.

To all the professors and colleagues in the RG2 and RG3 groups, in which I include

Mr. Carlos Torres, who in one way or another contributed to this work, I thank the regard

with which I was received and all the support provided.

A special mention to Ana Rita Figueira, for being a ‘partner in crime’, for the contagious good mood, invaluable lessons and always prompt and unconditional

assistance that cannot be put into words.

To Professor Fernanda Borges and Alexandra Gaspar, for kindly welcoming me into

their group and providing me with the necessary tools for what was to be a brief

collaboration and ended up becoming a long ‘synthetic’ endeavor.

To Joana, Tiago, Maria João and Sílvia, for representing the purest definition of

friendship. The past years wouldn’t have been the same without you.

To my loving parents and my dear B, for the never ending patience, encouragement,

support and love. For the constant reminder that it would all be worth it.

Again and always, to Professor Alice.

Thanks are also due to the Department of Chemistry and Biochemistry of the Faculty

of Sciences, University of Porto, and to CIQ-UP (Centro de Investigação em Química), for

providing the facilities and conditions necessary for the execution of this work.

And, finally, to FCT (Fundação para a Ciência e Tecnologia) for the award of the Ph.

D. research grant (SFRH/BD/80372/2011), included in the research project PTDC/QUI-

QUI/102814/2008, and for granting the financial support for the presentation of this research

in international scientific conferences.

VI

FCUP

VII

General index

Page

Abstract III

Resumo IV

Acknowledgments V

General index VII

Figure index XV

Table index XX

1. Introduction 1

1.1. Aim of the study 3

1.2. Compounds studied 4

1.3. Methods used 7

References 9

2. Synthesis 13

2.1. Introduction 15

2.2. General information 15

2.2.1. Reagents and solvents 15

2.2.2. General procedures and instrumentation 15

2.2.3. Synthetic yields and purity degrees 17

2.3. Synthetic procedures 18

2.3.1. Halogenated fluorene derivatives 18

2.3.1.1. 2,7-Difluorofluorene 18

2.3.1.2. 2,7-Dichlorofluorene 19

2.3.1.3. 2,7-Diiodofluorene 19

2.3.1.4. 2-Chlorofluorene 20

2.3.1.5. 9-Chlorofluorene 24

2.3.1.6. 9-Iodofluorene 25

2.3.2. Halogenated fluorenone derivatives 27

References 28

3. Experimental methods 29

3.1. Purification and characterization 31

3.1.1. Purification methods 31

3.1.2. Purity analysis 31

VIII

3.2. Calorimetric methods 33

3.2.1. Differential calorimetry 33

3.2.1.1. Introduction to differential calorimetry 33

3.2.1.2. Power compensation calorimetry: Differential scanning calorimeter 34

3.2.1.2.1. Typical thermogram and treatment of experimental results 35

3.2.1.2.2. Calibration 36

3.2.1.2.3. Description of the apparatuses 37

3.2.1.2.4. Experimental procedure 38

3.2.1.3. Heat flux calorimetry: Calvet Microcalorimeter 39

3.2.1.3.1. Typical thermogram and treatment of