Table 3.

Oxidative coupling of benzene (1a) with acrolein (6a) catalyzed by Pd(II)/HPMoV. ^a

Entry	HPMoV	Ligand	Time/h	Yield/% b
				7a	8a
1	H4PMo11VO40·26H2O	DBM	1.5	59	5
2	H4PMo11VO40·26H2O	DBM	1	26	nd d
3	H4PMo11VO40·26H2O	DBM	2	45	18
4	H4PMo11VO40·26H2O	DBM	3	17	40
5c	H4PMo11VO40·26H2O	DBM	1.5	53	6
6	H4PMo11VO40·26H2O	None	1.5	33	nd d
7	H4PMo11VO40·26H2O	benzoylacetone	1.5	52	6
8	H4PMo11VO40·26H2O	acacH	1.5	48	1
9	H4PMo11VO40·26H2O	acacH	2	54	8
10e	H4PMo11VO40·26H2O	acacH	2	3	nd d
11f	H4PMo11VO40·26H2O	acacH	2	44	2
12	H5PMo10V2O40·28H2O	DBM	1.5	54	6
13	H6PMo10V3O40·30H2O	DBM	1.5	47	6
14	H7PMo8V4O40·28H2O	DBM	1.5	35	1
15	H5PW10V2O40·27H2O	DBM	1.5	ndd	nd d
16	H3PMo12O40·30H2O	DBM	1.5	24	nd d

^a A mixture of 1a (30 mmol) and 6a (1.5 mmol) was reacted in the presence of Pd(OAc)₂ (0.1 mmol, 6.7 mol %), HPMoV (0.02 mmol, 1.3 mol %), Na₂CO₃ (0.05 mmol, 3 mol %) and ligand (0.1 mmol, 6.7 mol %) under O₂ (1 atm) in EtCOOH (5 mL). ^b GC yield based on 6a used. ^c 1a (20 mmol) was used. ^d Not detected by GC. ^e The reaction was performed in the absence of Na₂CO₃. ^f NaOAc (0.08 mmol) was used instead of Na₂CO₃.