2,6-Di-tert-butyl-4-methylphenol → HCID 22645428, compound

Participants

Reaction Steps

A solution of 1-hexyl-3,4-dimethyl-4-(3-trifluoromethanesulfonyloxyphenyl)piperidine (Preparation 1, 1.5 g, 3.6 mmol) in 1,4-dioxan (17 mL) was de-oxygenated by evacuating and flushing with nitrogen five times. Vinyl tributyl tin (1.06 mL, 3.71 mmol) was added under stirring, followed by lithium chloride (456 mg, 10.76 mmol), tetrakis(triphenylphosphine)palladium(0) (catalytic) and 2,6-di-tert-butyl-4-methylphenol (2 crystals). The suspension was stirred under nitrogen and heated at reflux for ten hours. After cooling to room temperature the reaction mixture was quenched with aqueous ammonium hydroxide solution (50 mL, 1.0 M) and further diluted with ethyl acetate (50 mL). The phases were separated and the aqueous layer was further extracted with ethyl acetate (3×25 mL). The combined organics were dried (Na2SO4) and concentrated in vacuo. The residual oil was purified by column chromatography on silica gel (120 g) eluted with ethyl acetate:hexane:0.880 ammonia (39:60:1) to give the title compound as an oil (890 mg).

Provenance & Evidence