R1		R2		R3		Ar		% Yield
4a	H		H		H		-C6H5		80
4b	H		H		H		4-FC6H4-		81
4c	H		H		H		4-MeOC6H4-		74
4d	-CH3		H		H		-C6H5		63
4e	-CH3		H		H		4-FC6H4-		63
4f	-CH3		H		H		4-MeOC6H4-		60
4g	H		-CH3		H		-C6H5		75
4h	H		-CH3		H		4-FC6H4-		70
4i	H		-CH3		H		4-MeOC6H4-		73
4j	H		-CH3		-CH3		-C6H5		76
4k	H		-CH3		-CH3		4-FC6H4-		77
4l	H		-CH3		-CH3		4-MeOC6H4-		81

Reagents and conditions: (i) ArB(OH)₂ (4.5 equiv.), PdCl₂(PPh₃)₂, PCy₃, K₂CO₃, dioxane-water (3/1, v/v), reflux, 5 h.