Optimization of reaction conditions^a.

Entry	Deviation from std. conditions	% Yieldb	Entry	Deviation from std. conditions	% Yieldb
1	None	89	10	PC10 instead PC1	nr
2	PC2 instead PC1	81	11	PC11 instead PC1	Trace
3	PC3 instead PC1	67	12	PC12 instead PC1	nr
4	PC4 instead PC1	91	13	PC13 instead PC1	nr
5	PC5 instead PC1	89	14	20 mol% Cu(OTf)2	32
6	PC6 instead PC1	52	15	20 mol% Yb(OTf)3	36
7	PC7 instead PC1	58	16	No PC	nr
8	PC8 instead PC1	68	17	No light	nr
9	PC9 instead PC1	81

^aReaction conditions: styrene 1a (0.1 or 0.2 mmol), RAE 2a (1.5 equiv.), potassium organotrifluoroborate salt 3a (2 equiv.), Ir(ppy)₃ (3 mol%) in MeCN (0.1 M), 24 h irradiation with blue LEDs (λ_max = 456 nm).

^bYields were determined by ¹H NMR analysis using trimethoxybenzene as internal standard. Abbreviations: std, standard; nr, no reaction.