Water → 4-benzyl-6-[2-cyclopropyl-5-((2S,3S,4R,5R,6R)-3,4,5-tris-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-2-yl)-benzyl]-3,4-dihydro-2H-benzo[1,4]oxazine

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 4-benzyl-6-[2-bromo-5-((2S,3S,4R,5R,6R)-3,4,5-tris-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-2-yl)-benzyl]-3,4-dihydro-2H-benzo[1,4]oxazine (0.35 g, 0.38 mmol) in toluene:water (10:1 mixture, 10 mL) was added cyclopropylboronic acid (49.2 mg, 0.5731 mmol) tricyclohexylphosphine (26.7 mg, 0.0955 mmol), and potassium phosphate (0.28 g, 1.34 mmol). The reaction mixture was degassed for 45 min then palladium (II) acetate (8.5 mg, 0.03821 mmol) was added. After heating overnight at 100° C., the reaction mixture was cooled to room temperature and water (20 mL) was added. The resulting mixture was extracted with ethyl acetate (2×25 mL), washed with water and brine, then dried over sodium sulfate, concentrated and purified by column chromatography to furnish 4-benzyl-6-[2-cyclopropyl-5-((2S,3S,4R,5R,6R)-3,4,5-tris-benzyloxy-6-benzyloxymethyl-tetrahydro-pyran-2-yl)-benzyl]-3,4-dihydro-2H-benzo[1,4]oxazine (317 mg). The product was taken up for the next step without characterization.

Provenance & Evidence