Optimization of the reaction conditions^a.

Entry	Variation	Yield of 3/3ab (%)
1	None	66/8
2	H+ instead of Li+	44/8
3	Na+ instead of Li+	60/12
4	Li2CO3 instead of LiOMe/DTBP	48/20
5	KF instead of LiOMe/DTBP	38/40
6	2,6-Difluoropyridine instead of LiOMe/DTBP	22/36
7	Cu(OAc)2 instead of Cu(OTf)2	0/0
8	DCM instead of MeCN	0/0c
9	No DTBP	0/0
10	No LiOMe	58/8

^aReaction conditions: 1 (0.05 mmol, 1.0 equiv.), 2 (2.5 equiv.), Cu(OTf)₂ (2.5 equiv.), LiOMe (1.0 equiv.), 2,6-di-tert-butylpyridine (DTBP, 2.0 equiv.), MeCN (c = 25 mM), 18 h purple LEDs irradiation, 35 °C.

^bYields were determined by ¹⁹F NMR using 2-fluorotoluene (2.0 equiv.) as an internal standard.

^c12% yield of protodecarboxylation product fluorobenzene was observed.