Thiophenol → tert-butyl 6-[2-(phenylsulfanyl)ethyl]-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate

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Reaction Steps

tert-Butyl 6-(2-hydroxyethyl)-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate, (0.0488 g, 0.148 mmol) was dissolved in CH2Cl2 (5 mL) and stirred at rt. Triethylamine (5 mL) was added, followed by methanesulfonyl chloride (0.017 mL, 0.221 mmol, 1.50 equiv.). The reaction mixture was stirred for 2 h, and additional methanesulfonyl chloride (0.015 mL) was added. After 30 min, a mixture of thiophenol (0.065 mL, 0.592 mmol, 4.0 equiv.) and KOH (12 equiv.) in DMF (5 mL) was added, and the resulting mixture was stirred for 30 min. The reaction mixture was quenched with saturated aqueous NH4Cl, then the resulting mixture was extracted with CH2Cl2 (3×). The combined organic extracts were dried over MgSO4, filtered, and concentrated. The crude product was purified by PTLC (1 mm×20 cm×20 cm SiO2 plates, developed with 1:4 EtOAc:hexane) to give tert-butyl 6-[2-(phenylsulfanyl)ethyl]-1,4,5,6-tetrahydroazepino[4,5-b]indole-3(2H)-carboxylate (0.017 g) in 28% yield as a white solid. 1H NMR (300 MHz, CDCl3) δ 1.52, 2.92, 2.99, 3.17, 3.66-3.73, 4.28, 7.10-7.20, 7.25-7.41, 7.48; MS (ESI+) for C25H30N2O2S m/z 423 (M+H)+.

Provenance & Evidence