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
P. Camps et al., 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, Tetrahedron, 54(18), 1998, pp. 4679-4696
The geometries, olefin strain energies, heats of hydrogenation and rel
ative HOMO/LUMO energies of tricycle [3.3.0.0(3,7)]oct-1(5)-ene and re
lated compounds have been obtained by ab initio calculations using dif
ferent basis sets. Tetracyclo[5.2.1.0(2,6).0(3,8)]dec-7-ene, a new mem
ber of this series of highly pyramidalized alkenes, has been generated
and trapped as different Diels-Alder adducts; in the absence of a tra
pping agent, it gives the expected dimeric derivatives in a non-stereo
selective way and in low yield. For the first time, good yield cross-c
oupling 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 ana
lysis. (C) 1998 Elsevier Science Ltd. All rights reserved.