Systems with Nineteen Conjugated Atoms

Preliminary accounts of the preparation and chemistry of betaines 381 (R = H, Me) have appeared. Compound 381 (R = H) is obtained in high yield by oxidation of dihydronorcoralyne (382 R = H) with w-chloroper-benzoic acid. In a similar manner, ethanolic solutions of dihydrocoralyne (382 R = Me) are oxidized to betaine 381 (R = Me) by air. The study of these compounds has so far been restricted to their oxidation products. Photooxidation of betaine 381 (R = H) followed by borohydride reduction gives a high yield of the phthalideisoquinoline 383. Photooxidation of the 8-methylbetaine 381 (R = Me) gives papaveraldine derivatives (384 R = COMe, CO2Me). The mechanisms of these transformations are open to conjecture. 

Betaines of this class (389) are of particular interest in that they have been isolated from natural sources. The alkaloid corunnine (389 R =H, R = R = OMe) is obtained as violet needles, mp 255-257°C, from Glaucium 

8-methylbetaine 381 (R = Me) gives papaveraldine derivatives (384 R = COMe, C02Me). The mechanisms of these transformations are open to conjecture. 

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