Ir(III)-Photocatalyzed Stereoselective Synthesis of 2‑Azadienes

A photocatalyzed, stereoselective C–N bond formation reaction was developed to synthesize 2-azadiene scaffolds containing trifluoromethyl groups under mild reaction conditions. This current methodology employs the multitasking photocatalysis of fac-Ir(ppy)3 to generate iminyl radicals from bench-stable oxime-ester precursors via an energy transfer (EnT) mechanism. This iminyl radical is installed in the olefinic system as an N-linchpin without any prefunctionalization through a photoredox cycle. The advantages of the reaction consist of mild aerobic reaction conditions, broad scopes, high yield, and impressive stereoselectivity.