Table 1.

Effects of the light source and the ketone catalyst on the benzylic fluorination of 1 and 2

Entry	Substrate	Catalyst	Light source	Time	Yield[i]
1	1	9-fluorenone	1 × CFL[a]	24 h	89% (85%)[j]
2	1	–	1 × CFL[a]	24 h	0%
3	2	9-fluorenone	1 × CFL[a]	24 h	80% (76%)[j]
4	2	–	1 × CFL[a]	30 h	89%
5	2	–	16 × RPR-3000Å[b]	30 min	46%
6	2	–	16 × RPR-3500Å[c]	1 h	73%
7	2	–	16 × RPR-4190Å[d]	6 h	96%
8	1	acetophenone	16 × RPR-4190Å[d]	6 h	88%
9	1	acetophenone	16 × RPR-4190Å[d,e]	20 h	70%
10	1	acetophenone	16 × RPR-4190Å[d,f]	20 h	0%
11	1	acetophenone	1 × violet LED[g]	3 h	85%
12	1	acetophenone	1 × CFL[a]	20 h	61%
13	1	acetophenone	1 × CFL[a,e]	20 h	50%
14	1	acetophenone	1 × CFL[a,f]	20 h	0%
15	1	acetone	1 × CFL[a}	20 h	0%
16	1	acetophenone	–[h]	24 h	0%

^[a]19 W, household lamp.

^[b]21 W, 250–375 nm.

^[c]24 W, 300–420 nm.

^[d]375–465 nm.

^[e]With a 375 nm longpass filter.

^[f]With a 400 nm logpass fileter.

^[g]9 W, 370–405 nm.

^[h]50 °C.

^[i]Determined by ¹⁹F NMR using C₆H₅F as an external standard.

^[j]Isolated yield.