Benzyl chloroformate → HCID 57828239, compound

Participants

Reaction Steps

A solution of carbamate 18 (2.0 g, 4.3 mmole) and 10% Pd/C (300 mg) in MeOH (60 mL) was subjected to hydrogenation conditions (50 psi) for 8 h at room temperature. The reaction mixture was filtered through a plug of diatomaceous earth and the plug was washed with MeOH (2×20 mL). The filtrate was then concentrated in vacuo to afford crude amine (1.4 g) which was dissolved in 1:1 CH2Cl2/NaHCO3 (saturated solution) (30 mL). Benzyl chloroformate (0.62 mL) was added dropwise at room temperature and the reaction mixture was stirred for 1 h. The mixture was concentrated, the residue was dissolved in EtOAc (500 mL), and the solution was washed with water (300 mL) and brine (300 mL). The organic layer was dried over Na2SO4, filtered, and concentrated. The residue was purified by column chromatography (silica gel, 4:1 hexanes/EtOAc) to afford butylcarbamate 19 (1.5 g, 77%) as a light yellow oil: 1H NMR (300 MHz, DMSO-d6) δ 8.24 (m, 1H), 7.91 (d, J=7.4 Hz, 1H), 7.51-7.42 (m, 2H), 7.34-7.28 (m, 5H), 7.12 (d, J=7.6 Hz, 1H), 6.77 (d, J=7.6 Hz, 1H), 5.08 (br s, 2H), 4.75 (br s, 1H), 3.22 (q, J=6.4 Hz, 2H), 2.99 (q, J=7.4 Hz, 2H), 1.76-1.71 (m, 2H), 1.67-1.56 (m, 2H), 1.09 (s, 9H), 0.27 (s, 6H).

Provenance & Evidence