Theoretical oxidative dimerization products of tryptamine

The sole isolable products were i//-chimonanthine from one dimer and the meso- form from the other. 

Despite the unwillingness of the rings to rearrange in the case of chimonanthine the synthesis of calycanine does involve such a rearrangement which is accomplished by heating /euco-isoindigo in hydrochloric acid. Lithium aluminium hydride reduction and selenium dehydrogenation completed the scheme. The structures of calycanthine and chimonanthine have been derived independently of any chemical assumptions by X-ray diffraction analysis. 

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