Potassium Carbonate → HCID 18338256, compound

Participants

Reaction Steps

The title compound was prepared from the corresponding triflate (which was prepared from (N-(Toluene-4-sulfonyl)-L-prolyl-L-tyrosine tert-butyl ester as taught by Tilley and coworkers, J. Org. Chem., 55, 906, 1990). The dipeptide (505 mg, 0.8 mmol.), a catalytic amount of tetrakis(triphenylhosphine)palladium(0), potassium carbonate (201 mg, 1.5 eq.), phenylboronic acid (199 mg, 2.0 eq.), and 15 mL of toluene were refluxed for 10 hours with stirring. Ethyl acetate was added and the organic layer was washed with water, 1N NaOH, brine and dried over magnesium sulfate. Upon filtration, the solvent was evaporated under reduced pressure. The crude material was purified on a preparative plate (1:1 ethyl acetate:hexanes). The silica gel was washed several times with acetonitrile and ethyl acetate. The combined fractions were evaporated and the residue was dried under reduced pressure.

Provenance & Evidence