https://pubs.rsc.org/en/Content/ArticleLanding/2016/OB/C6OB01942K
Synthesis of 6-substituted 2-phenacylpyridines from 2-(phenylethynyl)pyridine via...
When 2-(phenylethynyl)pyridine was oxidized, the formed N-oxide immediately cyclized at the ethynyl group to form isoxazolo[2,3-a]pyridinium salt. This salt...
synthesissubstitutedpyridinevia