Oxadiazolone-Enabled Synthesis of Primary Azaaromatic Amines

Despite their tremendous synthetic
and pharmaceutical utility,
primary azaaromatic amines remain elusive for access based on a generally
applicable C–H functionalization strategy. An oxadiazolone-enabled
approach is reported for convenient entry into N-unsubstituted 1-aminoisoquinolines
through Co­(III)-catalyzed redox-neutral, step-, atom-, and purification-economic
C–H functionalization with alkynes. A 15N labeling
experiment reveals the effectiveness of both oxadiazolone N atoms
as directing sites. The installed primary amine can be harnessed as
a synthetically useful handle for attachment of divergent appendages.