A-Ketoenamines reactions

Reaction of cyclic / -ketoenamines with diethyl diazene dicarboxylate is observed to yield Michael-type adducts85,86 (equation 61). For aromatization of the products see Section II.A.5. In contrast, the corresponding a-ketoenamine reaction leads to heterocyclic Diels-Alder adducts (see Section IV). 

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