Triphenylphosphine → [3-(2,6-Difluoro-3-nitrophenoxy)propyl]carbamic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 2,6-difluoro-3-nitrophenol (170 mg, 0.971 mmol) and triphenylphosphine (383 mg, 1.46 mmol) in THF (8 mL) was added a solution of (3-hydroxypropyl)carbamic acid tert-butyl ester (204 mg, 1.165 mmol) in THF (1 mL). The mixture was cooled in an ice bath and a solution of diethyl azodicarboxylate (255 mg, 1.46 mmol) in THF (1 mL) was added. The reaction was stirred at RT for 30 min, then concentrated in vacuo. The resulting residue was purified by column chromatography (Si—PCC, eluant 25-40% EtOAc in cyclohexane) affording the title compound as a colourless gum (296 mg, 92%). 1H NMR (CDCl3, 300 MHz): 7.81 (1H, ddd, J=9.4, 7.8, 5.3 Hz), 7.04 (1H, dt, J=9.4, 2.2 Hz), 4.77 (1H, bs), 4.27 (2H, t, J=6.0 Hz), 3.37 (2H, q, J=6.4 Hz), 2.00 (2H, quintet, J=6.3 Hz), 1.45 (9H, s)

Provenance & Evidence