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

HRID 877508Notes

Reaction equation

[Br:1][C:2]1[CH:7]=[CH:6][C:5]([NH:8]N=C2CCCCC2=O)=[C:4]([C:17]([F:20])([F:19])[F:18])[CH:3]=1.OS(O)(=O)=O.[C:26]([O-:29])(O)=O.[Na+]>CC#N>[Br:1][C:2]1[CH:7]=[C:6]2[C:5](=[C:4]([C:17]([F:18])([F:19])[F:20])[CH:3]=1)[NH:8][C:7]1[C:26](=[O:29])[CH2:5][CH2:4][CH2:3][C:2]2=1

Participants

Conditions

Temperature: 80 °C

Procedure

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).

Workup

temperaturecooled to room temperature
extractionextracted with EtOAc (2×30 mL)
dry with materialThe combined organic extracts were dried over Na2SO4
concentrationconcentrated in vacuo
customto give the crude compound which
customwas purified by silica gel chromatography [EtOAc-hexane (19:1) as eluant]

Sources & evidence

ORD record: ord-6c6b4dc2bd184d9c839f53e1b330aacc
Source dataset: uspto-grants-2015_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08987319B2

Reaction notes

Loading…