Table 1.

Optimization of reaction conditions^a.

Entry	Change to “condition A”	Yield (%)b
1	Condition A	73
2	No light	0
3	No photocatalyst	0
4	Without K2CO3	0
5	A,B,C,D instead of G	0
6	E, F, H instead of G	20–64
7	Other bases instead of K2CO3	0–49
8	Other solvents instead of DMF	0–55

^aUnless noted, the reactions were carried out using 1a (0.1 mmol), 2a (3 equiv), photocatalyst (1 mol %), base (3.0 equiv), and DMF (1 ml), under Ar, and stirred at rt for 12 h under 24-W violet LED irradiation.

^bIsolated yields.