Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

Twistane (Tricyclo[4.4.0.0 3,8 ]decan)

Philipp Emig Hendrik Schneider Marcel Meub Bastian Becker

1 Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

General Informations:

Name Tricyclo[4.4.0.0 3,8 ]decan

Chemical Formula C10 H16

Molecular Weight 136,237 g/mol

Melting Point ~163°C

Boiling Point 60°C (16 Torr)

State Solid

Twistane is a cyclic, double bridged, chiral with the molecular formula C 10 H16 which exists in the „twist conformation“. First it was synthesized in 1962, 29 years after his was found in crude oil. Since Adamantane is used in the plastic industry, as lube oil, and also as a pharmaceutical, people searched for a connatural industrial benefit, but this stayed away.

Since 1981, it just exists a patent on 3-amino-4-homoisotwistane, an antiviral agent, which kills bacteria outside of living organisms.

2 Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

Structure

Twistane consists of a double bridged carbon 6 ring, whith 2 carbon atoms per bridge. It is a hydrocarbon with the molecular formular C 10 H16 which is existent in the „twist-conformation“. It features a D 2 point group that implies three C 2 axes. It is often used as a paradigm for this group.

Stereochemical characteristics

Twistane owns 4 chiralic centres, which normally would admit 16 diasteromeres. But only 2 of them actually exist. This results from the extreme strong hoop stress, symmetry aspects as well as from the inelastic bonds in the molecule. It exists in a R,R,R,R,-Form and a S,S,S,S,-Form.

3 Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

Synthesis

2,7-dihydroxynaphtalane (I) is catalytic reduced to the diol IIa and oxidated to the diketone IIb.

In the next step the diketone IIb is ketalized to monoketal IIc and diketal IId, but just IIc is necessary for twistane synthesis.

Monoketal IIc is reduced to the analogical alcohol IIIa and subsequently mesylated to IIIb.

4 Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

Hydrolisation of ketal mesylate IIIb leads to keto mesylate IV.

Following the keto mesylate cyclisizes by treatment with sodium hydride whereas the tricyclic ketone V is delivered.

Finally the product is isolated by a Wolff-Kishner-Reduction.

At laboratory twistane can be synthesized by mixing an etheral solotuion of 1-twistyle chlorid with ammonia and adding sodium in small pieces over a view hours. After adding Ethanol, hydrochloric acid, extracting with pentane, washing, drying and destilling, the product can be found as a yellow residue.

5 Twistane Philipp Emig, Hendrik Schneider, Marcel Meub, Bastian Becker Damocles SS 2009

Sources

[1] http://uchv.upjs.sk/studium/studfiles/stereochemistry/symetria.htm [2] http://www.h-roth-kunst.com/ http://www.h-roth-kunst.com/essays/2007_StuPra_02_Chiralitaet.pdf http://www.h-roth-kunst.com/essays/2008_StuPra_09_Symmetrie_versus.pdf [3] Remarkable methyl substituent effect in a twistane aldol synthesis John D. Yordy, William Reusch J. Org. Chem., 1975, 40 (14), pp 2086–2088 [4] A new synthesis of twistane Jean Gauthier and Pierre Deslongchamps Department of Chemistry, University of Montreal, Montreal, Quebec Received August 24, 1966 [5] Syntheses of 8-acetoxy-4-twistanone, twistane, I-twistanol, 1-twistylamine, and I-twistanne carboxylic acid A. Bélanger, Y. Lambert and P. Deslongchamps Déparfement de Chirnie, Uniiversité de Sherbrooke, Sherbrooke, Quebec Received October 1, 1968 [6] http://pubs.acs.org/doi/abs/10.1021/jo00902a016 [7] http://en.wikipedia.org/wiki/Twistane [8] http://www.molecular-networks.com/software/theresa/examples/twistane_CCR2005.html [9] Solutions to Problems Elements of Synthesis Planning Springer Berlin Heidelberg R.W. Hoffmann Phillips Universität Marburg FB Chemie 2008

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