Synthesis of Aristotelia‐Type Alkaloids. Part XIII. Total syntheses of (+)‐makonine, (+)‐aristotelinone, and (+)‐11,12‐didehydroaristoteline

The oxidative transformation of synthetic (+)‐aristoteline ((+)‐6) into other metabolites which had been isolated from Aristotelia species was investigated. Thus, treatment of (+)‐6 with I2 as the single oxidant furnished the naturally occurring indole alkaloids (+)‐makonine ((+)‐9),(+)‐aristotelinone ((+)‐11), or (+)‐11, 12‐didehydroaristoteline ((+)‐7) in good yields, the selectivity of the oxidation process depending on the chosen reaction conditions.