Sulfuric Acid → 7,8-Dichloro-2,3,4,9-tetrahydro-1H-carbazol-1-one

HRID 877494Notes

Reaction equation

[Cl:1][C:2]1[C:7]([Cl:8])=[CH:6][CH:5]=[CH:4][C:3]=1[NH:9]N=C1CCCCC1=O.OS(O)(=O)=O.[C:23]([O-:26])(O)=O.[Na+]>CC#N>[Cl:8][C:7]1[C:2]([Cl:1])=[C:3]2[C:4]([C:2]3[CH2:3][CH2:4][CH2:5][C:23](=[O:26])[C:7]=3[NH:9]2)=[CH:5][CH:6]=1

Participants

Conditions

Temperature: 80 °C

Procedure

To a solution of 2-(2-(2,3-dichlorophenyl)hydrazono)cyclohexanone (1.6 g, 5.9 mmol) in MeCN (10 mL), H2SO4 (0.6 mL, 0.01 mmol, 1.6M solution) was added and the reaction mixture was stirred at 80° C. for 16 h, cooled to room temperature, basified with NaHCO3 and extracted with EtOAc (2×20 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 (1:4) as eluant] to provide the title compound as a solid (0.90 g, 60%). 1H NMR (200 MHz, DMSO-d6, δ in ppm) 12.13 (bs, 1H), 7.72 (d, J=8.8 Hz, 1H), 7.31 (d, J=8.8 Hz, 1H), 2.99 (t, J=8.4 Hz, 2H), 2.62-2.2.56 (m, 2H), 2.21-2.12 (m, 2H).

Workup

temperaturecooled to room temperature
extractionextracted with EtOAc (2×20 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 (1:4) as eluant]

Sources & evidence

ORD record: ord-0cefbd6a33ed439181615571dc468cfb
Source dataset: uspto-grants-2015_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08987319B2

Reaction notes

Loading…