Synthesis of Tubular, Belt-like and Möbius Aromatics

191 Pages·2004·17.15 MB·English

Synthesis of Tubular, Belt‐like and Möbius Aromatics 

Von der Gemeinsamen Naturwissenschaftlichen Fakultät 
der Technischen Universität Carolo‐Wilhelmina 
Zu Braunschweig 

Zur Erlangung des Grades eines 
Doktors der Naturwissenschaften 
(Dr.rer.nat.) 
genehmigte 
Dissertation

Von 
Dariush Ajami 
Aus Teheran
1. Referent:    Prof. Dr. Rainer Herges 
2. Referent:    Prof. Dr. Henning Hopf 
eingereicht am:    17. October 2003 
Mündliche Prüfung (Disputation) am: 07. November 2003
To my parents and Mina
Danksagung 

  Mein besonderer Dank für die sehr angenehme und konstruktive Atmosphäre 
gilt meinem Doktorvater Prof. Dr. Rainer Herges. Er hat mich während der gesamten 
Arbeit stets mit Interesse, Anregungen und einem immer offenen Ohr unterstützt. 

  Meinen Arbeitskreiskollegen Dr. Torsten Winkler, Dr. Markus Diechmann, 
Felix Köhler, Dr. Anke Krüger, Regina Meinlschmeit, Birtta Harbaum, Kirsten Hess, 
Katrin Schluze, Dietmund Peters, Monika Bayerhuber, Jan Clausen, Jörg Taubitz 
gebührt mein Dank für die sehr freundschaftliche Zusammenarbeit.  
  Beim technischen Personal in Braunschweig und Kiel möchte ich mich für die 
Bereitstellung der Chemikalien, die Herstellung von Glasgeräten und die Messung 
zahlreicher Spektren bedanken.
1. Introduction......................................................................................................................1

1.1. History of Aromaticity............................................................................................1

1.2. Spherical Aromatic Compounds...........................................................................3

1.3 Tubular and Belt-like Aromatic Compounds......................................................4

1.3.1 Nanotubes.........................................................................................................4

1.3.1.1 Straight nanotubes...........................................................................................5

1.3.1.2 Helix-shaped and Hemitoroidal nanotube..................................................6

1.3.2 Cyclacenes, Beltenes and Collarenes............................................................8

1.3.3 Picotubes...........................................................................................................8

1.3.4 Cylic [n]paraphenylacetylenes......................................................................9

1.3.5 Bowl-shaped Benzoannulenes.....................................................................10

1.4 Our approach.........................................................................................................10

2 9,9’,10,10’-Tetradehydrodianthracene (TDDA) as the building block of picotubes

syntheses.................................................................................................................................15

2.1 Synthesis of TDDA................................................................................................15

2.1.1 Greene’s synthesis of TDDA........................................................................15

2.1.2 Neumann’s improvement of the TDDA synthesis...................................16

2.1.3 Synthesis of o-mesitylensulfonylhydroxylamine (Carpino’s reagent)..16

2.2. Characterization....................................................................................................17

2.3 Reactivity................................................................................................................19

2.3.1 Electrophilic addition to TDDA..................................................................19

2.3.2 Nucleophilic addition to TDDA..................................................................19

2.3.3 Diels-Alder reaction of TDDA.....................................................................20

2.3.3.1 Diels-Alder reaction with electron-rich dienes.........................................20

2.3.3.2 Diels-Alder reaction with electron-poor dienes........................................21

2.3.4 Photochemically induced metathesis reactions of TDDA.......................22

2.3.4.1 Photochemical reaction with cycloalkenes................................................22

2.3.4.2 Photodimerization of TDDA.......................................................................22

2.3.4.3 Synthesis of Kammermeierphane...............................................................23
2.4. Conclusion:.............................................................................................................24

3 9,9’,9’’,10,10’,10’’-Hexadehydrotrianthracene (Trimer)...........................................25

3.1 General....................................................................................................................25

3.2 Synthesis strategy..................................................................................................26

3.3 Synthesis of the semitrimer..................................................................................33

3.4 Complexation properties of the semitrimer......................................................38

3.5 Epoxidation of semitrimer...................................................................................40

3.6 Attempted synthesis of Trimer from Semitrimer.............................................41

3.7 Attempted photochemically induced metathesis reactions of the semitrimer

43

3.8 Conclusion;.............................................................................................................43

4 Photochemically induced metathesis reaction of the tetramer...............................45

4.1 Improvement of the tetramer synthesis.............................................................46

4.3 Photochemically induced metathesis reaction of the tetramer.......................53

4.2 Photoreaction of tetramer in micellar solution.................................................55

4.3 Irradiation of the tetramer in aliphatic solvents...............................................57

4.4 Solid phase irradiation of the tetramer..............................................................57

4.5 Calculated structures of the hexamer and the octamer...................................62

4.7 Conclusion..............................................................................................................65

5 Möbius Aromatic compounds.....................................................................................67

5.1 General....................................................................................................................67

5.2 Möbius topologies in chemistry..........................................................................68

5.2.1 Möbius-type conjugation in annulenes......................................................68

5.2.2 Application of the Hückel-Möbius concept in organic chemistry.........69

5.2.3 Theoretically calculated Möbius annulenes..............................................71

5.2.4 A double-stranded Möbius strip of carbon and oxygen atoms..............75

5.2.5 Möbius strip of a single crystal....................................................................75

5.3 Synthesis of Möbius aromatic compound.........................................................76

5.3.1 Proposed strategy for synthesizing Möbius aromatic compounds.......77
5.3.2 Photochemically induced metathesis reactions of TDDA and

cyclooctatetraene...........................................................................................................79

5.3.3 Synthesis of cis- or trans-tricyclooctadiene................................................82

5.3.4 Photochemically induced metathesis reactions of TDDA with cis-

tricyclooctadiene............................................................................................................83

5.3.4.1 Photochemically induced metathesis reactions with using high pressure

mercury lamp.................................................................................................................83

5.3.4.2 Photochemically induced metathesis reactions using a low-pressure

mercury lamp.................................................................................................................90

5.3.5 Quantitative Measures of Aromaticity.......................................................99

5.3.5.1 Calculated energy of isomers......................................................................99

5.3.5.2 Harmonic oscillator model of aromaticity (HOMA)..............................102

5.3.5.3 Nucleus independent chemical shift (NICS)...........................................104

5.3.5.4 Magnetic susceptibility...............................................................................104

5.3.5.5 Anisotropy of current induced density....................................................104

5.3.5.6 UV absorption spectra................................................................................107

5.4 Conclusion........................................................................................................108

6 Summary.......................................................................................................................109

7 Experimental part........................................................................................................115

7.1 Apparatus.............................................................................................................115

7.2 Common procedure............................................................................................116

7.3 Synthesis...............................................................................................................117

7.3.1 Synthesis of TDDA......................................................................................117

7.3.1.1 Synthesis of 9-bromoanthracene...............................................................117

7.3.1.2 Synthesis of 9,10’-dibromoanthracene......................................................117

7.3.1.3 Synthesis of bistriazolindianthracene.......................................................118

7.3.1.4 Synthesis of N-aminobistriazolindianthracene.......................................118

7.3.1.5 Synthesis of tetradehydrodianthracene...................................................119

7.3.2 Synthesis of o-mesitylensulfonylhydroxylamin (Carpino’s reagent)..120
7.3.2.1 Synthesis of tert-butyl phenyl carbonate..................................................120

7.3.2.2 Synthesis of tert-butyl carbazate...............................................................120

7.3.2.3 Synthesis of tert-butyl azidoformate.........................................................121

7.3.2.4 Synthesis of tert-butyl N-hydroxycarbamate..........................................122

7.3.2.5 Synthesis of tert-butyl N-p-toluenesulfonoxycarbamate.......................122

7.3.2.5 Synthesis of hydroxylamine o-mesitylene sulfonate (Carpino’s reagent)

123

7.3.3 Attempted Diels-Alder reaction................................................................124

7.3.3.1 Typical reaction...........................................................................................124

7.3.3.2 Attempted Diels-Alder using ultrasound................................................124

7.3.3.3 Solid phase reaction under microwave irradiation................................125

7.3.3.4 Attempted high-pressure Diels-Alder reaction......................................125

7.3.3.5 Attempted solid phase Diels-Alder reaction...........................................125

7.3.4 Solid support reactions...............................................................................125

7.3.4.1 Addition of toluene to TDDA in the presence of Montmorillonite k10

125

7.3.4.2 Addition of anthracene to TDDA in the presence of Montmorillonite

k10 126

7.3.4 Step by step synthesis of the trimer..........................................................127

7.3.4.1 Synthesis of the semitrimer 14...................................................................127

7.3.4.2 Complexation of the semitrimer...............................................................128

7.3.4.3 Epoxidation of the semitrimer...................................................................128

7.3.4.4 Attempted conversion of the semitrimer to the trimer by Heck reaction

130

7.3.4.4 Attempted bromination of the semitrimer..............................................130

7.3.4.5 Irradiation of the semitrimer and TDDA.................................................130

7.3.5 Photochemically induced metathesis reaction of tetramer...................131

7.3.5.1 Synthesis of the tetramer............................................................................131

7.3.5.2 Irradiation of the tetramer in micelles......................................................131
7.3.5.3 Irradiation of tetramer in dodecane..........................................................132

7.3.5.4 Solid phase irradiation of the tetramer with a laser...............................132

7.3.6 Synthesis of Möbius aromatic compounds..............................................132

7.3.6.1 Irradiation of TDDA and cyclooctatetraene............................................132

7.3.6.2 Thermal reaction of TDDA and cyclooctatetraene.................................133

7.3.6.3 Synthesis of the syn-tricyclooctadiene......................................................133

7.3.6.4 Irradiation of TDDA and TCOD with 700 W high-pressure mercury

lamp 133

7.3.6.5 Irradiation of TDDA and TCOD with 15 W low-pressure mercury lamp

135

7.4 X-ray structure data............................................................................................138

7.4.1 X-ray structure of compound 10...............................................................138

7.4.2 X-ray structure of the semitrimer 14.........................................................141

7.4.3 X-ray structure of tetramer 4.....................................................................146

7.4.4 X-ray structure of the C closed isomer 36...............................................151
2

7.4.5 X-ray structure of isomer 38.......................................................................158

7.4.6 X-ray structure of the C Möbius 39..........................................................165
1

7.4.7 X-ray Structure of the C Möbius 40.........................................................173
2

8. References.....................................................................................................................182
1. Introduction 

Since the discovery of the fullerenes in 1985[1] and the generation of carbon nanotubes 
by Iijima in 1991[2], the synthesis of the fully conjugated non‐planar hydrocarbons 
gained  tremendous  interest.  The  fullerenes  as  well  as  the  nanotubes,  so  far,  are 
prepared  at  very  high  temperatures.  Under  these  crude  conditions  a  number  of 
different structures (different diameter, length, helicity etc) are formed alongside 
with  amorphous  carbon.  In  case  of  the  fullerenes  efficient  separation  techniques 
made it possible to isolate C  and C  in larger amounts and high purity, however, 
60 70
the  purification  of  carbon  nanotubes  is  still  a  distant  prospect  (except  on  the 
molecular level by single molecule manipulation in an AFM device). 
The  rational  synthesis  of  carbon  nanotubes  obtain  uniform  structures  with  well 
defined  physical  properties  is  considered  to  be  one  of  the  “holy  grails”  of 
nanotechnology[3]. The present work is aimed at taking the first steps toward this 
ambitious goal. 

1.1.  History of Aromaticity 
Fullerenes and carbon nanotubes are aromatic compounds. Aromaticity is also an 
important property of the belt‐like compounds, which are the targets of the present 
study. Therefore, a short history of the development of this concept is given below: 

1825  Isolation of benzene (Faraday)[4]
1865  Benzene structure (Kekule)[5]
1866  Substitution is more favourable than addition (Erlenmeyer)[6]
1910  Aromatic compounds have exalted diamagnetic susceptibilities (Pascal)[7]
1925  Electron sextet and heteroaromaticity (Armit‐Robinson)[8]