Table 4. Optimization of the Reaction Conditions^a.

entry	catalyst	solvent	T (°C)	yield(%)b
1	Pd(OAc)2/PPh3	DMF	135	40
2	Pd(OAc)2/PPh3	DMSO	135	48
3	Pd(OAc)2/PPh3	DMA	135	36
4	Pd(OAc)2/PPh3	p-xylene	135	82
5	Pd(OAc)2/PPh3	p-xylene	145	78
6	Pd(OAc)2/PPh3	p-xylene	125	38
7	Pd(OAc)2	p-xylene	135	21
8	PdCl2/PPh3	p-xylene	135	57
9	Pd(dppf)Cl2/PPh3	p-xylene	135	72

^aReaction conditions: Pd salt (0.015 mmol, 0.075 equiv), ligand (0.03 mmol, 0.15 equiv), 1c (0.2 mmol, 1.0 equiv), 1e (0.30 mmol, 1.5 equiv), and Cs₂CO₃ (0.4 mmol, 2.0 equiv) in solvent (2.0 mL) under the N₂ atmosphere for 24 h.

^bIsolated yield after flash chromatography based on 1c.