Stereoselective Synthesis of Diaza-Hexatrienes via [1,6]- <i>O</i> -to- <i>N</i> Group Transfer Strategy

Herein, we report a transition metal-free synthesis of <i>Z</i>-configured 2,3-diaza-1,3,5-hexatrienes via a base-mediated rearrangement of <i>O</i>-substituted salicylaldehyde <i>N</i>-tosylhydrazones. This unprecedented <i>O</i>-to-<i>N</i> group transfer occurs under mild conditions, exhibits a broad substrate scope, and tolerates diverse functional groups. The resulting diazatrienes serve as precursors for heterocycles and photoswitches. This rearrangement introduces a new synthetic strategy distinct from classical phenol-based rearrangements.