Synthesis and Photochemistry of Heterocyclic Norbornenyl Ketones

Article abstract of DOI:10.1021/jo00234a001

A series of endo-5-norbonenyl ketones 1 was prepared which contained the following heterocyclic rings: 2-furyl, 2-thienyl, N-methyl-2-pyrryl, 3,5-dimethyl-4-isoxazolyl, 5-methyl-3-isoxazolyl and 2,5-dimethyl-4-oxazolyl groups.Oxetanes 2 were produced from the ketones either by direct irradiation (λ > 300 nm) or by use of photosensitizers.The two isoxazolyl systems were irradiated at 254 nm and found to lead to additional products, two of which were identified as 2H-azirines 16.It is probable that the latter were formed from an upper level excited state.