Hydrochloric Acid → 1-(4-Acetylaminosulfonylphenyl)-2-(3,4-dimethylphenyl)-4-methylpyrrole

Temperature

70 °C

3.26 g (13.1 mmol) of 3-(3,4-dimethylbenzoyl)-2-methylpropionaldehyde ethylene acetal [prepared as described in step (ii) above] and 2.81 g (13.1 mmol) of 4-acetylaminosulfonylaniline were dissolved in a mixture of 52 ml (52 mmol) of 1N aqueous hydrochloric acid and 16 ml of tetrahydrofuran, and the mixture was heated at 70° C. for 1 hour. At the end of this time, the mixture was left to stand to allow it to cool. The mixture was then extracted three times with ethyl acetate. The organic extracts were combined and washed with a saturated aqueous solution of sodium chloride. The resulting solution was then dried over anhydrous magnesium sulfate, after which it was concentrated by evaporation under reduced pressure. The residue thus obtained was applied to a silica gel chromatography column and eluted with a 3:2 by volume mixture of hexane and ethyl acetate and crystallised from diisopropyl ether, to give 1.27 g (yield 25%) of the title compound as a white powder, melting at 192-193° C.

1. waitAt the end of this time, the mixture was left
2. temperatureto cool
3. extractionThe mixture was then extracted three times with ethyl acetate
4. washwashed with a saturated aqueous solution of sodium chloride
5. dry with materialThe resulting solution was then dried over anhydrous magnesium sulfate
6. concentrationafter which it was concentrated by evaporation under reduced pressure
7. customThe residue thus obtained
8. washeluted with a 3:2 by volume mixture of hexane and ethyl acetate
9. customcrystallised from diisopropyl ether

ORD record

ord-4425c5057c7348d584a4beee6f48a745

Source dataset

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

USRE039420E1