Table 9.

Preparation of Homoallylic Alcohol Products from Nickel-Catalyzed Alkene–Aldehyde Couplings ^a

entry	alkene	aldehyde	major product (2)	yield (%)(2:2′) b,c	E:Z (2) b
1 d		PhCHO	2a	73 (89:11)	n.a
2		PhCHO	2b	85 (95:5)	75:25
3 e				72 (>95:5)	75:25
4 e		p-anisaldehyde	2c	85 (>95:5)	75:25
5 e		p- Cl(C6H4)CHO	2d	37 (>95:5)	74:26
6 f		2-naphthaldehyde	2e	88 (>95:5)	70:30
7		1-methyl-2-indole- carboxaldehyde	2f	56 (>95:5)	83:17
8 f		t-BuCHO	2g	64 (>95:5)	78:22
9		PhCHO	2h	86 (92:8)	>95:5
10		o-anisaldehyde m-anisaldehyde p-anisaldehyde	2i (ortho) 2i (meta) 2i (para)	78 (92:8) 98 (92:8) 99 (92:8)	>95:5 >95:5 >95:5
11 f,g		p-anisaldehyde	2i (para)	98 (92:8)	>95:5
12 f		2-naphthaldehyde	2j	88 (95:5)	>95:5
13		1-methyl-2-indole-carboxaldehyde	2k	57 (>95:5)	>95:5
14		t-BuCHO	2l	65 (>95:5)	78:22
15		p-anisaldehyde	2m	91 (92:8)	69:31
16		PhCHO	2n	82 (>95:5)	81:19
17			2o	95 (86:14) h	n.a.
18			2p	99 (75:25) h	n.a.
19			3q	14 (>95:5) i	n.a.

^aStandard procedure: (entries 1–8, 15–18): To a solution of Ni(cod)2 (0.1 mmol) and EtOPPh₂ (0.2 mmol) in toluene (2.5 mL) at 23 °C under Ar were added the alkene (0.5 mL), triethylamine (3.0 mmol), the aldehyde (0.5 mmol), and Et₃SiOTf (0.875 mmol). The mixture was stirred 48 h at room temperature and purified by chromatography (SiO₂). Entries 9–14: Ph₃P was used in place of EtOPPh₂.

^bYields were determined by ¹H NMR using DMF as a standard.

^cSee Supporting Information for structures of the minor products (2a′-2p′).

^dPropene (1 atm) was used in place of Ar.

^eReaction time 18 h.

^fReaction temperature 35 °C.

^gFivefold larger reaction scale.

^hratio of 2:3.

ⁱratio of 3: (2q+2q′).