Triethylamine → 2,6-Dimethyl-4-[[[3-[[(1,1-dimethylethyl)dimethylsilyl]oxy]benzyl]amino]carbonyl]benzoic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of trifluoromethanesulfonic acid, 2,6-dimethyl-4-[[[3-[[(1,1-dimethylethyl)dimethylsilyl]oxy]benzyl]amino]carbonyl]phenyl ester (Example 105, 562 mg, 1.09 mmol) in acetonitrile (7 mL) and water (1 mL) at 25° C. was added palladium (II) acetate (24 mg, 0.109 mmol), 1,3-bis(diphenylphosphino)propane (45 mg, 0.109 mmol), followed by triethylamine (2.18 mmol, 0.303 mL). The reaction was then pressurized to 40 psi with carbon monoxide and heated to 80° C. for 4 h. The mixture was diluted with ethyl acetate (100 mL) and washed with water (50 mL) containing 1 mL of triethylamine. The separated aqueous layer was re-extracted with ethyl acetate (2×50 mL) and the combined organic layers were discarded. The aqueous phase was adjusted with 1N hydrochloric acid solution to pH 2 and extracted with ethyl acetate (100 mL). The organic extract was washed with water (25 mL) and brine (25 mL), dried (MgSO4), filtered and evaporated under reduced pressure to yield 2,6-dimethyl-4-[[[3-[[(1,1-dimethylethyl)dimethylsilyl]oxy]benzyl]amino]carbonyl]benzoic acid (1.7 g, 71% yield) as a colorless solid.

Provenance & Evidence