The Diels-Alder reaction of 1, 2, 3, 4-tetrachloro-5, 5-< limethoxycyclopenta-1, 3-diene with cyclopropene has been utilized to furnish some endo-tricyclo [3.2. 1.02, 4] octane derivatives. Several exo-tricyclo [3.2. 1.2, 4] octane derivatives were synthesized from known precursors using standard reactions. The stereochemistry of the tetracyclic alcohol, resulting (ultimately) from the reaction of 7-norbornadienyl acetate with diazomethane, is discussed ...