Control experiments^a.

Entry	Additive	Yield B1b (%)
1	C6F5I (4.0 equiv.)	95
2	C6F5Br (4.0 equiv.)	N. D.
3	C6F5I (4.0 equiv.) + C6F5Br (4.0 equiv.)	72
4	C6F5I (4.0 equiv.) + KBr (3.0 equiv.)	82
5	C6F5Br (4.0 equiv.) + nBu4NI (3.0 equiv.)	N. D.
6	C6F5I (4.0 equiv.) + TEMPO (1.0 equiv.)	<2%
7	C6F5I (4.0 equiv.) + galvinoxyl (1.0 equiv.)	N. D.

^aReaction conditions: A1 (0.2 mmol), 3DPAFIPN (0.012 mmol), additive, K₂CO₃ (0.6 mmol), CH₂Cl₂ (1 mL) in a 4 mL reaction vial, irradiated with a 34 W Kessil blue LED for 24 h under fan cooling.

^bMeasured by GC using dodecane as an internal standard.