Aza-di-7i-methane rearrangement

For more than 30 years, di-7i-methane processes were limited to the three different types of (3,y-unsaturated systems mentioned above. However, recent studies have shown that the rearrangement is applicable to 2-aza-1,4-dienes [13]. Thus, triplet-sensitized irradiation of compound 11 affords the cyclopropylimine 12 and the TV-vinylaziridine 13 (Sch. 6). The photoreaction of 11 represents the first example of a 2-aza-di-7i-methane rearrangement (2-ADPM) that brings about the formation of a heterocyclic product. The reaction has been extended to other 2-azadienes that yield the corresponding cyclopropylimines regioselectively [13b]. 

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