Bidetraasteran

Structural formula
General
Surname	Bidetraasteran
other names	Nonacyclo [10.8.0.0 2.11 .0 4.9 .0 4.19 .0 6.17 .0 7.16 .0 9.14 .0 14.19 ] eicosan
Molecular formula	C 20 H 24
Brief description	colorless needles
External identifiers / databases
CAS number 110318-58-6 Wikidata Q70898882
properties
Molar mass	264.19 g mol −1
Physical state	firmly
Melting point	230-235 ° C
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Bistetraasteran is a saturated polycyclic C ₂₀ H ₂₄ - hydrocarbon with a cage-like structure from the group of Asterane .

presentation

The preparation of bis-tetraasterane, which is based on the synthesis concept of tetraasterane from 1975, was described in 1987. The starting compound is dimethylene cyclohexene 1 , which is reacted with acetylenedicarboxylic acid 2 in dioxane in the sense of a Diels-Alder reaction . In this reaction, the anhydride of the tetrahydronaphthalene compound 3 is obtained directly in a yield of 60% . Exposure of this anhydride in the presence of benzophenone to a high- pressure mercury lamp gives an isomer mixture of at least four dimers with a yield of 8%, which contains compound 4 in a proportion of 46%. The bisanhydride 4 can be hydrolyzed to the tetracarboxylic acid 5 in 90% yield with sodium hydroxide solution . The reaction with lead tetraacetate and N -chlorosuccinimide in the sense of a Kochi reaction according to a variant of Grob yields the tetrachloro compound 6 , which is contaminated with a pentachloro compound which is not further characterized. With sodium in a mixture of ethanol and THF as solvent, the dehalogenation to the bis-tetraasterane 7 succeeds in a yield of 21%.

Multi-step synthesis of bisasterane

properties

In the bis-tetraasterane, the eight interconnected cyclohexane rings are fixed in the boat conformation. Just as the compounds adamantane or diamondane can be seen as sub-segments of the diamond lattice , tetraasterane and bis-tetraasterane are parts of a hypothetical carbon modification with a tetraasterane lattice. While in the diamond lattice the horizontal and vertical planes are formed by cyclohexane rings in the energetically more favorable chair conformation, in the tetraasterane lattice the cyclohexane rings would be present in both the horizontal and vertical layers in the boat conformation.

Bidetraasteran can be purified by sublimation at 80–100 ° C and 0.3 mbar and crystallizes from methanol in colorless needles.

Individual evidence

1. ↑ ^{a b c d} Volker Thomas Hoffmann, Hans Musso: Asterane, XXII. Synthesis of a double tetraasterane: Nonacyclo [10.8.0.0 ^2.11 .0 ^4.9 .0 ^4.19 .0 ^6.17 .0 ^7.16 .0 ^9.14 .0 ^14.19 ] eicosane . In: Chemical Reports . tape 124 , no. 1 , January 1991, pp. 103 , doi : 10.1002 / cber.19911240118 .
2. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
3. ↑ Volker T. Hoffmann: Synthesis of Nonacyclo [10.8.0.0 ^2.11 .0 ^4.9 .0 ^4.19 .0 ^6.17 .0 ^7.16 .0 ^9.14 .0 ^14.19 ] eicosane (Bis -Tetraasteran) . Dissertation, University of Karlsruhe (TH). Karlsruhe 1987.
4. ↑ Volker T. Hoffmann, Hans Musso: nonacyclo [10.8.0.0 ^2,11 .0 ^4,9 .0 ^4,19 .0 ^6,17 .0 ^7,16 .0 ^9,14 .0 ^14,19 ] -icosan , a double tetraasterane . In: Angewandte Chemie . tape 99 , no. 10 October 1987, p. 1036 , doi : 10.1002 / anie.19870991008 .
5. ^ Günther Kaiser, Hans Musso: Asterane, XVII. On the synthesis of [4] propellane derivatives of tetraasterane . In: Chemical Reports . tape 118 , no. 6 June 1985, pp. 2266 , doi : 10.1002 / cber.19851180610 .