Sodium Azide → tert-Butyl 6-(2-azidoethyl)-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

tert-Butyl 6-{2-[(methylsulfonyl)oxy]ethyl}-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.224 g, 0.549 mmol) and NaN3 (0.357 g, 5.49 mmol, 10.0 equiv.) were dissolved in DMF (2.5 mL) and the solution was stirred at 60° C. under N2 for 14.5 h. The reaction mixture was taken up in EtOAc and washed with water (2×15 mL). The aqueous layers were back extracted with EtOAc (25 mL). The combined organic layers were washed with brine (10 mL), dried over MgSO4, filtered and concentrated. The crude product (0.214 g) was chromatographed (SiO2 25 g, eluted with 3:1 hexane:EtOAc) to give tert-butyl 6-(2-azidoethyl)-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.184 g) in 94% yield. 1H NMR (300 MHz, CDCl3) δ 1.51, 2.99-3.10, 3.60, 3.66-3.84, 4.26, 7.14, 7.21, 7.27, 7.51; MS (ESI+) for C19H25N5O2 m/z 356.2 (M+H)+.

Provenance & Evidence