反应详情

To a refluxing solution of 9.20 g (40.0 mmoles) of 2,6-dichloro-4-trifluoromethylaniline and 0.76 g (4.0 mmoles) of p-toluenesulfonic acid monohydrate in 25 mL of benzene was added dropwise over an 8 hour period with a syringe pump 9.40 mL (9.14 g, 80.1 mmoles) of acetonylacetone. Throughout the addition, water was removed via a Dean-Stark trap. The reaction mixture was then cooled and partitioned with a saturated aqueous solution of NaHCO3 which was back-extracted with ether. The combined organic layers were dried over anhydrous Na2SO4 concentrated. The residual brown oil was chromatographed on silica gel with a 95:5 v/v hexane-EtOAc eluent to afford 10.0 g (81%) of 1-(2,6-dichloro-4-trifluoromethylphenyl)-2,5-dimethylpyrrole as a light brown solid of melting point 63° C.

1. customwas removed via a Dean-Stark trap
2. temperatureThe reaction mixture was then cooled
3. custompartitioned with a saturated aqueous solution of NaHCO3 which
4. extractionwas back-extracted with ether
5. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
6. concentrationconcentrated
7. customThe residual brown oil was chromatographed on silica gel with a 95:5 v/v hexane-EtOAc eluent