Triethylamine → Methyl (2S)-2-[(benzyloxy)carbonyl]amino-3-[3-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]propanoate

Participants

Reaction Conditions

Reaction Steps

To a mixture of methyl (2S)-2-[(benzyloxy)carbonyl]amino-3-(4-bromo-3-methylphenyl)propanoate (1.23 g, 3.03 mmol), 1,4-dioxane (8 mL), triethylamine (1.69 mL, 12.1 mmol), palladium acetate (17 mg, 76 μmol), O-(dicyclohexylphosphino)biphenyl (106 mg, 0.303 mmol) was added 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1.10 mL, 7.57 mmol) dropwise. The greenish reaction mixture was stirred at 80° C. for 30 min. The reaction was quenched with saturated NH4Cl solution. The aqueous solution was extracted with ethyl acetate twice. The organic solutions were washed with brine, dried with sodium sulfate, filtered, and concentrated in vacuo. The crude residue was purified by flash column chromatography to yield the desired product (1.25 g, 91%). 1H NMR (400 MHz, CDCl3): δ 7.67 (d, 1H), 7.3 (m, 5H), 6.9 (m, 2H), 5.22 (d, 1H), 5.10 (m, 2H), 4.64 (m, 1H), 3.70 (s, 3H), 3.06 (m, 2H), 2.48 (s, 3H), 1.33 (s, 12H); MF=C25H32BNO6; LCMS found for C25H33BNO6 (M+H)+: m/z=454.

Provenance & Evidence