4-Chlorophenol → tert-Butyl 6-[2-(4-chlorophenoxy)ethyl]-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate

Participants

Reaction Steps

tert-Butyl 6-(2-hydroxyethyl)-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.533 g, 1.61 mmol), p-chlorophenol (0.224 g, 1.74 mmol, 1.08 equiv.) and triphenylphosphine (0.445 g, 1.70 mmol, 1.05 equiv.) was dissolved in THF (10 mL) and stirred at rt under N2. Diethyl azodicarboxylate (0.30 mL, 0.337 g, 1.93 mmol, 1.2 equiv.) was added, and the reaction mixture was stirred for 2.5 h. The reaction mixture was concentrated to give crude product (1.85 g), which was chromatographed (SiO2 175 g, eluted with 4:1 hexane:EtOAc) to give tert-butyl 6-[2-(4-chlorophenoxy)ethyl]-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.622 g) in 88% yield. 1H NMR (300 MHz, CD3OD) δ 1.48, 2.96-3.03, 3.05-3.14, 3.63-3.78, 4.15, 4.48, 6.70, 7.11, 7.15-7.20, 7.17, 7.27-7.31, 7.46-7.51; MS (ESI+) for C25H29ClN2O3 m/z 440.9 (M+H)+.

Provenance & Evidence