Centrohexaindane: six benzene rings mutually fixed in three dimensions - solid-state structure and six-fold nitrationElectronic supplementary information (ESI) available: 1H NMR spectra (250 MHz) and EI (70 eV) mass spectra of the mixtures of compounds 6 and 7 and compounds 8-10, and of compounds 11 and 12; 1H NMR spectra (500 MHz), 13C NMR spectra (126 MHz), 1H,1H-COSY spectra; (−)-ESI mass spectra of compounds 14-17; and illustrations of the space-filling structures of 1 and with a co-crystall
The solid-state molecular structure of centrohexaindane ( 1 ), a unique hydrocarbon comprising six benzene rings clamped to each other in three dimensions around a neopentane core, and the molecular packing in crystals of 1 ·CHCl 3 are reported. The molecular T d -symmetry and the Cartesian orientat...
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| Main Authors | , , , , , , , , |
|---|---|
| Format | Journal Article |
| Published |
28.04.2016
|
| Online Access | Get full text |
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| Summary: | The solid-state molecular structure of centrohexaindane (
1
), a unique hydrocarbon comprising six benzene rings clamped to each other in three dimensions around a neopentane core, and the molecular packing in crystals of
1
·CHCl
3
are reported. The molecular
T
d
-symmetry and the Cartesian orientation of the six indane wings of
1
in the solid state have been confirmed. The course and limitation of electrophilic aromatic substitution of
1
are demonstrated for the case of nitration. Based on nitration experiments of a lower congener of
1
, tribenzotriquinacene
5
, the six-fold nitrofunctionalisation of
1
has been achieved in excellent yield, giving four constitutional isomers, two nonsymmetrical (
14
and
17
) and two
C
3
-symmetrical ones (
15
and
16
), all of which contain one single nitro group in each of the six benzene rings. The relative yields of the four isomers (∼3 : 1 : 1 : 3) point to a random electrophilic attack of the electrophiles at the twelve formally equivalent outer positions of the aromatic periphery of
1
, suggesting electronic independence of its six aromatic π-electron systems. In turn, the pronounced conformational rigidity of the centrohexacyclic framework of
1
enables the unequivocal structural identification of the isomeric hexanitrocentrohexaindanes
14-17
by
1
H NMR spectroscopy.
The solid-state structure of centrohexaindane,
1
, and the sixfold nitration of this three-dimensional polycyclic and topologically nonplanar hydrocarbon is reported. |
|---|---|
| Bibliography: | C NMR spectra (126 MHz) 1436523 xylene and H H NMR spectra (250 MHz) and EI (70 eV) mass spectra of the mixtures of compounds 8-10 and compounds H-COSY spectra; (−)-ESI mass spectra of compounds For ESI and crystallographic data in CIF or other electronic format see DOI and 14-17 1436522 11 12 13 Electronic supplementary information (ESI) available 10.1039/c5cp07005h , p 1 CHCl H NMR spectra (500 MHz) 1436470 3 6 7 0.5 ; and with a co-crystallised solvent molecule as well as of the molecular packing in the crystals of triethylamine. CCDC and of compounds and illustrations of the space-filling structures of |
| ISSN: | 1463-9076 1463-9084 |
| DOI: | 10.1039/c5cp07005h |