Optimization and control reactions^a.

Entry	Solvent	Atm.	Time (h)	Yieldb (%)
1	Toluene	Air	24	9
2	THF	Air	24	54
3	DMSO	Air	24	23
4	DMF	Air	24	52
5	EtOAc	Air	24	84
6	DCM	Air	24	56
7	Acetone	Air	24	91
8	PEG200	Air	24	20
9	Glycerol	Air	24	5
10	Water	Air	24	57
11	Methanol	Air	24	100
12	Ethanol	Air	24	100
13c	Ethanol	Air	24	0
14	Ethanol	Nitrogen	24	20
15	Ethanol	Oxygen	24	100
16 d	Ethanol	Air	18	100 (89) e
17d	Ethanol	Oxygen	18	100
18d	Ethanol	Air	12	61
19d	Ethanol	Oxygen	12	94

^aReaction conditions: 1a (0.15 mmol), 2a (0.75 equiv.), solvent (2 mL) at room temperature irradiated with 3 W blue LED (467 nm).

^bYields obtained by GC using internal standard method.

^cReaction performed under dark.

^d0.5 equiv. of 2a were used.

^eIsolated yield.