Fig. 4: Scope of arene substituents.

Reaction conditions: 3 (0.2 mmol, 1 equiv.), 2,4,6-collidine (0.4 mmol, 2 equiv.), PC-I (7.5 mol%), Co(dmgH)2(py)2PF6 (10 mol%), DCE (2.0 mL, 0.1 M), rt, blue LEDs, 48–72 h.
Reaction conditions: 3 (0.2 mmol, 1 equiv.), 2,4,6-collidine (0.4 mmol, 2 equiv.), PC-I (7.5 mol%), Co(dmgH)2(py)2PF6 (10 mol%), DCE (2.0 mL, 0.1 M), rt, blue LEDs, 48–72 h.