ca01 only detailed ToC 1..24

1.1.4 Nickel–Alkene Complexes 71
[5,5¢-Bi(bicyclo[2.2.1]hept-2-en)-6-yl-kC 6 -6¢-olato-kO](2,2¢-bipyridyl-k 2 N 1 ,N 1 ¢)nickel (84): [153]
A sample of 83 (0.35 g, 0.94 mmol) and benzene (10 mL) were placed in a round-bottomed
flask attached to a swivel-frit assembly. The soln was stirred under N 2O (1 atm) at 55 8C for
3 d, after which the soln was filtered and the filtrate was taken to dryness under vacuum.
The resulting solid was washed with petroleum ether (3 ” 5 mL), and the blue product was
collected on a filter frit to give microcrystalline 84; yield: 0.16 g (44%).
exo-trans-endo-3-Oxapentacyclo[9.2.1.1 5,8 .0 2,10 .0 4,9 ]pentadeca-6,12-diene (85): [153]
A sample of 84 (0.12 g, 0.31 mmol) and benzene (10 mL) were placed in a round-bottomed
flask, to which I 2 (0.08g, 0.31 mmol) was added under an argon counterflow. There was an
immediate color change from blue to brown. The soln was stirred for 30 min at rt and filtered,
and the filtrate was evaporated using a rotary evaporator. The residue was chromatographed
(silica gel, hexane/EtOAc 100:3) to give 85 as a colorless oil; yield: 0.03 g
(47%).
(1R*,2S*,3R*,5R*)-2-Benzoyl-3-phenylbicyclo[3.3.0]octane-3-ol (90, R 1 = Ph);
Typical Procedure: [131]
A mixture of 2.44 M BuLi in hexane (0.43 mL, 1.05 mmol) and 1.0 M ZnCl 2 in Et 2O (0.70 mL,
0.70 mmol) in THF (5 mL) was stirred for 1 h at 08C. A soln of [Ni(cod) 2] (2; 3mg,
0.01 mmol) in THF (2 mL) was added by syringe, and the resulting soln was immediately
transferred by cannula to a soln of 89 (91 mg, 0.30 mmol) in THF (3 mL) at 08C. After stirring
for 1.5 h at 0 8C the deep red mixture was quenched with sat. NaHCO 3 (20 mL), extracted
with EtOAc (3 ” 25 mL), dried (Na 2SO 4), filtered, and concentrated. The residue
was chromatographed (silica gel, Et 2O/pentane 1:15) to afford 90 (R 1 = Ph) as a white crystalline
solid; yield: 56 mg (60%).
Dimethyl 3-Methyl-4-methylenecyclopentane-1,1-dicarboxylate (93,R 1 =CO 2Me);
Typical Procedure: [160]
The catalyst precursor was prepared as follows. To a soln of [{Ni(allyl)Br} 2] (4.2 mg,
0.012 mmol, 2.5 mol%, 0.05 equiv in Ni) in CH 2Cl 2 (1 mL) was added tris(4-methoxyphenyl)phosphine
(8.5 mg, 0.024 mmol) in CH 2Cl 2 (1 mL). The mixture was stirred for 30 min, after
which AgOTf (6 mg, 0.024 mmol) was added in one lot. After 30 min of stirring, a precipitate
was formed (AgBr), which was subsequently removed by filtration through a pipet
containing a plug of Celite. The catalyst was cooled to –348C and introduced into a
soln of 92 (100 mg, 0.47 mmol) in CH 2Cl 2 (2 mL) at rt. The soln was stirred at rt for 2 h, after
which the reaction was stopped and the mixture was concentrated. Analysis of the crude
product showed it to be 92% of the expected product 93 and 8% starting material. The
crude product was chromatographed on a column (silica gel, hexane/Et 2O 9:1) to afford
pure 93 (R 1 =CO 2Me); yield: 92 mg (92%).
1.1.4.4 Method 4:
Alkene Carbonylation
The carbonylation of alkenes proceeds readily upon treatment of an alkene with a nickel
catalyst in the presence of carbon monoxide and an alcohol or water (Scheme 70). [7,11,104]
Tetracarbonylnickel(0) is the most commonly used nickel catalyst, although it is highly
toxic. [188] This process is very useful for the carbonylation of simple alkenes such as
ethene, but it has seen little use with complex organic molecules.
Scheme 70 Carbonylation of Alkenes [104]
H 2C CH 2 + CO + H 2O
Ni
CO 2H
for references see p 79