Table 1.

Optimization of reaction conditions^a

Entry	L	L (%)	Solvent	T/(oC)	Yield (%)	L:B (3a:4a)
1	—	—	toluene	30	18	>20:1
2	PPh3	10 mol%	toluene	30	17	>20:1
3	PPh3	5 mol%	toluene	30	96	>20:1
4	PCy3	5 mol%	toluene	30	38	>20:1
5	BPY	5 mol%	toluene	30	<5	—
6	1,10-phen	5 mol%	toluene	30	<5	7:1
7b	L1	5 mol%	toluene	30	81	>20:1
8	L2	5 mol%	toluene	30	20	>20:1
9	L3	5 mol%	toluene	30	trace	—
10	BINAP	8 mol%	toluene	30	NR	—
11	BINAP	5 mol%	toluene	30	96	>1:20
12	BINAP	4.7 mol%	toluene	30	96	>1:20
13	BINAP	2.5 mol%	toluene	30	90	1:9
14	BINAP	5 mol%	DMA	30	trace	—
15	BINAP	5 mol%	MeOtBu	30	59	>1:20
16	BINAP	5 mol%	dioxane	30	95	>1:20
17	BINAP	5 mol%	DCE	30	NR	—
18	BINAP	5 mol%	THF	30	<5	—
19	BINAP	5 mol%	EtOH	30	NR	—
20	BINAP	5 mol%	toluene	0	NR	—
21c	BINAP	5 mol%	toluene	30	60	>1:20
22c	PPh3	5 mol%	toluene	30	81	>20:1

^aReaction conditions: 1a (0.2 mmol), 2a (0.4 mmol), Ni(cod)₂ (5 mol%), L (x mol%), 30 ^oC in solvent (2.0 mL) under argon, 24 h, L:B value was determined by ¹⁹F NMR, isolated yield.

^bCsOAc (20 mol%).

^c2a (0.2 mmol).