Nickel-catalyzed hydrosilation of alkenes^a,b.

Entry	Ni (mol%)	Olefin	Silane	t (h)	Yieldc, %
1	0.56	Cyclopentene	Ph2SiH2	18	26
2d	0.56	Cyclopentene	Ph2SiH2	1	98
3	0.56	tBuCH CH2	Ph2SiH2	1	97
4e	0.56	4-methyl-1-pentene	Ph2SiH2	1	96
5f	0.56	1-hexene	Ph2SiH2	1	98
6f	0.10	1-hexene	Ph2SiH2	17	97
7g	0.23	1-hexene	Ph2SiH2	3	98
8	0.56	Cyclopentene	PhMeSiH2	0.5	92
				28	98
9	0.56	tBuCH CH2	Et2SiH2	26	99
10h	0.56	4-methyl-1-pentene	Ph2MeSiH	1.5	98
11	1.0	Cyclopentene	Ph2MeSiH	2	98
12	0.56	tBuCH CH2	Ph2MeSiH	2	98
13	0.56	Cyclopentene	R2MeSiH (R = Me3SiO)	1.5	98
14	3.0	Cyclopentene	Ph2ClSiH	42	90
				65	95
15i	0.56	Cyclopentene	PhSiH3	20	22
				41	30
16i	0.56	Cyclopentene	MesSiH3	1.1	75

^aHydrosilation catalysis was carried out using 3a, except entry 1 which involves 3b.

^bGeneral conditions: entries 1–6 and 9, silanes (1.27 equiv.), 23 °C, C₆D₅Br; entries 8 and 10–16, silanes (1.27 equiv.), 23 °C, o-C₆H₄Cl₂.

^cYields were determined by NMR spectroscopy by integrating the product signals against an internal standard, and the identities of the products were confirmed by GC-MS. Where more than one hydrosilation product is generated, yields represent the combination of both products.

^dIn addition to Ph₂SiH(cyclopentyl), Ph₂Si(cyclopentyl)₂ (<5%) was also formed.

^eHydrosilation product distribution: Ph₂SiH(CH₂)₃CH(CH₃)₂ and Ph₂Si[(CH₂)₃CH(CH₃)₂]₂ (5.3 : 1 ratio).

^fHydrosilation product distribution: Ph₂SiH(CH₂)₅CH₃ and Ph₂Si[(CH₂)₅CH₃]₂ (3 : 1 ratio).

^gThe reaction was carried out without solvent; hydrosilation product distribution: Ph₂SiH(CH₂)₅CH₃ and Ph₂Si[(CH₂)₅CH₃]₂ (7.3 : 1 ratio).

^hSmall amounts (ca. 8%) of unidentified products in addition to the hydrosilation product were observed.

ⁱIn addition to the expected hydrosilation product, small amounts of cyclopentane and other unidentified silicon-containing products were observed.