Chemistry of 2-Carbenabicyclooctadiene

Article abstract of DOI:10.1021/jo00132a011

Pyrolytic decomposition of the lithium or potassium salt of the tosylhydrazone of bicyclo<3.2.1>octa-3,6-dien-2-one (11) or photolysis of the lithium salt of 11 results in the formation of bicyclo<3.2.1>octa-2,6-diene (12), tricyclo<3.2.1.0^2,7>oct-3-ene (13), tetracyclo<3.3.0.0^2,8.0^4,6>octane (14), semibullvalene (15), 5-ethynyl-1,3-cyclohexadiene (16), and endo-6-ethynylbicyclo<3.1.0>hex-2-ene (17).The formation of the C8H8 fraction (15-17) is ascribed to insertion and rearrangement reactions of singlet 2-carbenabicyclo<3.2.1>octadiene, whereas the formation ofthe C8H10 fraction (12-14) appears to be the result of hydrogen abstraction reactions of the corresponding triplet carbene or closely related species.