Tributylamine → 3-[2-(tert-Butoxycarbonylamino-methyl)-phenyl]-but-2-enoic Acid Ethyl Ester

Participants

Reaction Conditions

Reaction Steps

N-Boc-2-bromobenzylamine (7.15 g, 25 mmol) was dissolved into tributylamine (12 mL) and degassed under vacuum. Palladium acetate (224 mg, 1 mmol) and tri-o-tolylphosphine (608 mg, 2 mmol) was then added and the mixture degassed under vacuum. Trans-ethylcrotonate (6.25 mL, 50 mmol) was then added and the mixture was degassed with nitrogen. The tube was sealed and the mixture was heated to 110° C. for 48 h. The solution was cooled to room temperature, diluted with diethyl ether (200 mL) and filtered through celite. The solution was washed with 1N HCl (2×50 mL) and brine (50 mL) dried over magnesium sulfate and concentrated to dryness. Flash chromatography (9:1 hexanes/ethyl acetate) gave the title compound as a yellow oil (1.6 g, 20%). 1H NMR 7.22-7.37 (m, 3H), 7.08 (dd, J=7.4, 1.6 Hz, 1H), 5.75 (d, J=1.3 Hz, 1H), 4.29-4.31 (m, 2H), 4.20 (q, J=7.1 Hz, 2H), 2.45 (d, J=1.3 Hz, 3H), 1.44 (s, 9H), 1.30 (t, J=7.1 Hz, 3H).

Provenance & Evidence