Jacques A. Zuber

Evidence for homoquadricyclene, a possible carbon ylide

Abstract The endo-epimer of the formal homo-1,4 adduct of monochlorocarbene and norborna-2,5-diene on treatment with lithium 2,2,6,6-tetramethylpiperidide in THF in the presence of diphenylisobenzofurane (DPIBF) gave a single Diels-Alder adduct. The same cyclo-adduct was obtained by subjecting the homo-1,4 adduct of dibromocarbene and norborna-2,5-diene to lithiummethyl in THF. By single crystal X-ray analysis the adduct is shown to be the result of the normal Diels-Alder cyclo-addition of DPIBF to the least hindered side of tetracyclo[3.2.1.0. 2,7 0. 4,6 ]oct-2-ene, a novel anti-Bredt olefine, best considered as a carbon ylide.

The deceptive rearrangement of a C8H9 cation of the cage type

We produce evidence to show that the acetolysis of exo-seco-cubyl mesylate gives 7-tetracyclo[3.3.0.02,8,03,6]octyl acetate as sole product and not 5-tetracyclo[4.2.0.02,403,8]-octyl acetate.