A slight modification of a literature procedure was used to synthesize 9. A reaction tube was charged with Ni(cod)2 (55.0 mg, 0.2 mmol), Me IPr tBu (105.8 mg, 0.2 mmol), and benzene (2 mL). The resulting solution was transferred into an autoclave reactor, and then H2 was pressurized quickly (recommended within 5 min) into the reactor at 50 atm. After the reaction mixture was stirred at room temperature overnight (∼16 h), the resultant red solution was filtered, and all volatiles were removed under reduced pressure to give [ Me IPr tBu -Ni(η 6 -C6H6)] as a reddish brown solid (126.0 mg, 0.189 mmol, 90% yield). In a glovebox, an oven dried screw-capped 2 mL vial was charged with a magnetic stir bar, [ Me IPr tBu -Ni(η 6 -C6H6)] 9 (10 μmol), degassed (free pump thaw) THF (0.1 mL) was then added ketone 1i (0.1 mmol degassed freeze pump thaw if the ketone is liquid) and COD 2a (0.2 mmol degassed by freeze pump thaw) was then added successively. The vial was sealed with a Teflon-lined screw cap, and running inside the glovebox at room temperature. After 24 h, the vial was shipped outside of the glovebox. The reaction mixture was diluted with dichloromethane and filtered through a plug of silica gel. The crude solution was concentrated in vacuum and subjected to column chromatography 100:1 PE/EA to isolate the products 3i with 65% yield and 6.3:1 dr.