Table 1. Optimization of reaction conditions ^a .

Entry	Reaction condition deviation	Vinylsilanes	Product	Yields of 15 (%)
1	None	7	15a	79 (72)
2	None	8	15b	51
3	None	9	15c	56
4	None	10	15d	0
5	None	11	15e	0
6	None	12	15f	0
7	None	13	15g	0
8	None	14	15h	0
9	15 h	7	15a	62
10	(cod)2Ni instead of NiBr2	7	15a	35
11	(Ph3P)4Ni instead of NiBr2	7	15a	30
12	DMF or DMA instead of NMP	7	15a	40–44
13	DMSO, dioxane or MeCN instead of NMP	7	15a	10–15
14	Benzene of THF instead of NMP	7	15a	<5
15	Cul or FeCl3 instead of NiBr2	7	15a	0
16	Pd(OAc)2 or Co(OAc)2 instead of NiBr2	7	15a	0 b

^aYields were determined by ¹H NMR using pyrene as an internal standard. Value in parenthesis is the isolated yield from a 0.5 mmol scale reaction.

^bHeck product was formed in >90% NMR yield with Co(OAc)₂.