Triethylamine → HCID 74788456, compound

Participants

Reaction Steps

To a solution of trans-[2-(2,5-dimethoxyphenyl)cyclopropylmethyl]carbamic acid tert-butyl ester (13) (4.20 g, 13.7 mmol) in CH2Cl2 (30 mL) at −78° C. was added BBr3 (1.0 M solution in CH2Cl2) (47.8 mL, 47.8 mmol) dropwise. The solution was warmed to rt, and the reaction mixture was quenched with MeOH (110 mL) and concentrated in vacuo. This process was repeated until no white fumes were observed upon addition of MeOH to give a crude product as pale yellow oils. The crude product was used without any further purification. A solution of the crude product, Boc2O (3.28 g, 15.0 mmol), and triethylamine (7.62 mL, 54.7 mmol) in CH2Cl2 (30 mL) was stirred at rt for 30 min. To the resulting mixture were added sat. aq NaHCO3, and the aqueous layer was extracted with CH2Cl2 (×2). The organic layer was further washed with water (×1), dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by flash chromatography using gradient elution from 0% EtOAc-hexane to 30% EtOAc-hexane to afford the title compounds as a pale yellow oil (2.55 g, 66.8% yield). 1H NMR (400 MHz, CDCl3) δ 6.73 (d, J=8.4 Hz, 1 H), 6.57 (dd, J=8.8 Hz, J=2.6 Hz, 1 H), 6.42 (d, J=2.6 Hz, 1 H), 5.01 (bs, 1 H), 4.45 (s, 1 H), 3.51-3.44 (m, 1 H), 2.92-2.85 (m, 1 H), 1.89-1.87 (m, 1 H), 1.47 (s, 9 H), 1.06-1.01 (m, 1 H), 0.92-0.90 (m, 1 H), 0.75-0.72 (m, 1 H).

Provenance & Evidence