A. Ashe
1969
Citations
0
Influential Citations
5
Citations
Journal
Tetrahedron Letters
Abstract
(Received in USA 30 September 1968; received in UK for publication 1 January 1769) There has been much interest in the synthesis of strained bicyclic hydrocarbons involving two relatively small trans-fused rings. The 7-4 system, trans-bicyclo[5.2.0]nonanel, the 6-4 system, trans-bicyclo[4.2.0]octane2, and the 5-4 system, trans-bicyclo[3.2.0]heptane2 have been synthesized. On the other hand the smallest compound with a trans-fused cyclopropane ring had been the 8-3 system, trans-bicyclo[6.1.0]octane.3 A recent preliminary report of the synthesis of trans-bicyclo[5.1.O]octane-4-carboxylic acid 1+ prompts us to report our data on the synthesis of trans-fused cyclopropanes. 5 The readily available trimer of butadiene, trans,trans,trans-1,5,$+cyclo-dodecatriene (I), can be stereospecifically converted to trans,trans,transbicyclo[lO.l.O]trideca-3,7diene (II) by the Simmons-Smith reaction. A Lenieux-Rudolph' oxidation of this diene Save an oily mixture of diacid III and succinic acid, which vlere converted without isolation to their dimethyl esters. In our hands the Dieckmann ring closure of diester IV failed. However, the acyloin reaction gave a lQ$ yield of a mixture of the trans-bicyclo[6.1.0]nonan-k-ones (V) and trans-bicyclo[6.1.0]nona-4,5-dione (VI). This mixture could be oxidized by cupric acetate to dione VI, which showed carbonyl absorption at 1710 cm-l (CCl4) in the IR. No enol could be detected in the golden yellow dione. 7