Formaldehyde → 7-(benzyloxy)-N-methyl-9H-carbazol-2-amine

Participants

Reaction Steps

A mixture of 7-(benzyloxy)-9H-carbazol-2-amine (150 mg, 0.52 mmol), paraformaldehyde (78 mg, 2.6 mmol), and NaOMe (900 mg, 25% MeOH solution, 4.16 mmol) in 15 mL of MeOH was heated at reflux for 2 h under Ar atmosphere and cooled to rt. To this mixture was added NaBH4 (98 mg, 2.6 mmol) and the mixture was heated at reflux for 2 h. After cooling to rt, the mixture was quenched onto ice (30 g). It was extracted with EtOAc (3×50 mL) and the combined organic phase was dried over MgSO4 and concentrated. The crude product was purified with chromatography (hexane/EtOAc) to afford 7-(benzyloxy)-N-methyl-9H-carbazol-2-amine as a light-brown solid (130 mg, 82%). 1H NMR (400 MHz, acetone-d6) δ 9.78 (s, 1H), 7.72 (d, J=8.4 Hz, 1H), 7.66 (d, J=8.8 Hz, 1H), 7.49 (d, J=7.2 Hz, 2H), 7.37 (m, 2H), 7.32-7.28 (m, 1H), 6.98 (d, J=2.4 Hz, 1H), 6.78 (dd, J=8.4, 2.4 Hz, 1H), 6.56 (d, J=2.0 Hz, 1H), 6.49 (dd, J=8.4, 2.4 Hz, 1H), 5.13 (s, 2H), 4.96 (s, 1H), 2.82 (s, 3H); MS (ESI) m/z 303 (M+H+).

Provenance & Evidence