Methylene aziridines allenimines

The photolysis of a homologous series of methylene aziridines (aliphatic alleni-mines) has been shown to proceed via two major types of molecular elimination 

The product ethylene is formed in a stoichiometric yield with the nitrile and isonitrile, and for methylallenimine, / (C2H4) = 0.25 and p(C2H2) = 0.13. The lower than unity efficiency appears to indicate that some deactivating mechanism is also operative. The overall mode of decomposition bears a close resemblance to that of the hydrocarbon analog, the methylenecyclopropane ring system. 

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