Ethylene Glycol → 8,9-Dichloro-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-benzoyl-8,9-dichloro-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole (2.00 g, 5.57 mmol), potassium hydroxide (3.00 g, 53.5 mmol), and ethylene glycol (15 mL) was heated to 170° C. After 2 h, the reaction was cooled to room temperature, diluted with H2O, and extracted with CH2Cl2. The combined organic extracts were washed with brine, dried over Na2SO4, decanted, and concentrated under reduced pressure. The crude product was purified by silica gel chromatography with CH2Cl2/MeOH/Et2NH (9:1:0 followed by 97:3:1 followed by 95:4:1) to give 1.04 g (73%) of 8,9-dichloro-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole as a dark yellow solid. 1H NMR (d-CHCl3) δ 7.75, 7.50, 7.34, 3.08, 2.92, 2.82, 1.91; MS (ESI) 255.1 (M++H).

Provenance & Evidence