Reactions and Rearrangements of the Vincadifformine Group

Although not strictly a rearrangement reaction, the behavior of (-)-vincadifformine (76) when heated in a sealed tube in a microwave oven is of interest. Almost quantitative racemization occurs, presumably via reversible Diels-Alder fission of ring C and the related achiral secodine intermediate (211). 

The structure of oxymetavincadifformine (283), the name now given (212) to the oxidative rearrangement product of vincadifformine (1), has been confirmed by X-ray crystal structure analysis. 

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