Highly pyramidalized tricyclo[3.3.0.0 3,7]oct-1(5)-ene and related compounds: High-level ab initio study, synthesis and trapping of tetracyclo[5.2.1.0 2,6.0 3,8] dec-7-ene, and cross-coupling reactions

Abstract

The geometries, olefin strain energies, heats of hydrogenation and relative HOMO/LUMO energies of tricyclo [3.3.0.0 3,7]oct-1(5)-ene and related compounds have been obtained by ab initio calculations using different basis sets. Tetracyclo-[5.2.1.0 2,6.0 3,8]dec-7-ene, a new member of this series of highly pyramidalized alkenes, has been generated and trapped as different Diels-Alder adducts; in the absence of a trapping agent, it gives the expected dimeric derivatives in a non-stereoselective way and in low yield. For the first time, good yield cross-coupling reactions among highly pyramidalized alkenes have been carried out. The structure of a tetrasecododecahedrane diepoxide derived from a cross-coupled product has been established by X-Ray diffraction analysis.