Sulfuric Acid → 5,6,7-Trichloro-2,3,4,9-tetrahydro-1H-carbazol-1-one

Participants

Reaction Conditions

Reaction Steps

2-(2-(3,4,5-Trichlorophenyl)hydrazono)cyclohexanone (1 g, 3.2 mmol) was dissolved in MeCN (10 mL) and aqueous H2SO4 (0.5 mL, 1.8M solution) was added. The reaction mixture was heated to 80° C. for 6 h, basified with saturated Na2CO3 and extracted with EtOAc (2×100 mL). The combined organic extracts were dried over Na2SO4 and concentrated under reduced pressure to give the crude material which was purified by silica gel column chromatography [EtOAc-hexane (1:9) as eluant] to give the title compound (0.15 g, 16%). 1H NMR (500 MHz, DMSO-d6, δ in ppm) 12.3 (bs, 1H), 7.58 (s, 1H), 3.24 (t, J=12.0 Hz, 2H), 2.59 (t, J=13.0 Hz, 2H), 2.19 (m, 2H).

Provenance & Evidence