Sulfuric Acid → 6-Bromo-8-(trifluoromethyl)-2,3,4,9-tetrahydro-1H-carbazol-1-one

Participants

Reaction Conditions

Reaction Steps

2-(2-(4-Bromo-2-(trifluoromethyl)phenyl)hydrazono)cyclohexanone (2 g, 5.73 mmol) was dissolved in MeCN (18 mL) and H2SO4 (1.68 g, 17.19 mmol) was added. The reaction mixture was heated to 80° C. for 32 h, cooled to room temperature, basified with saturated aqueous NaHCO3 (pH-8) and extracted with EtOAc (2×30 mL). The combined organic extracts were dried over Na2SO4 and concentrated in vacuo to give the crude compound which was purified by silica gel chromatography [EtOAc-hexane (19:1) as eluant] to provide the title compound as a pale green solid (750 mg, 39%). 1H NMR (200 MHz, CDCl3, δ in ppm) 9.0 (bs, 1H), 7.9 (s, 1H), 7.72 (d, 1H, J=0.8 Hz), 2.96 (t, J=12.0 Hz, 2H), 2.66 (t, J=12.8 Hz, 2H), 2.33-2.27 (m, 2H).

Provenance & Evidence