Phosphorus oxychloride → 1-(5-(4-chlorophenyl)-1,4-dimethyl-1H-pyrrol-2-yl)-2-cyclopropylethanone

Temperature

0 °C

POCl3 (1.36 g, 0.82 ml, 8.88 mmol) was added to 2-cyclopropyl-N,N-dimethylacetamide (prepared according to the procedure described in Nils SchrOder et al., J. Am. Chem. Soc., 2012, 134, 8298-8301), 1.13 g (8.88 mmol) at 0° C. and under stirring and the reaction was continued at 0° C. for 15 min. The reaction mixture was allowed to warm up to room temperature, stirred for 20 min, and diluted with 1,2-dichloroethane (10 ml). 2-(4-chlorophenyl)-1,3-dimethyl-1H-pyrrole (prepared according to the procedure described in Kazuhiko Taguchi et. al., Tetrahedron Letters, 2005, 46, 4539-4542) (1.64 g, 8.0 mmol) was dissolved in 1,2-dichloroethane (20 ml) and was added to the reaction mixture at 0° C. The reaction mixture was heated to reflux temperature (95° C.) for 30 min. The progress of the reaction was monitored TLC. The reaction mixture was cooled to room temperature. Sodium acetate (4.01 g, 48.9 mmol) was dissolved in water (15 ml) and added to the reaction mixture. The reaction mixture was stirred at 100° C. for 1 hr. The progress of the reaction was monitored by TLC. The reaction mixture was cooled to room temperature, diluted with DCM (50 ml) and water (20 ml) was added to it. The organic layers were separated, dried over anhydrous sodium sulfate, filtered and concentrated to obtain a crude product. This crude product was purified by column chromatography using 5-10% ethyl acetate in hexanes as an eluent to obtain the title compound 3(0.77 g, 30.5%). MS: m/z 288 (M+1).

1. customprepared
2. temperatureto warm up to room temperature
3. stirringstirred for 20 min
4. additionwas added to the reaction mixture at 0° C
5. temperatureThe reaction mixture was heated
6. temperatureto reflux temperature (95° C.) for 30 min
7. temperatureThe reaction mixture was cooled to room temperature
8. additionadded to the reaction mixture
9. stirringThe reaction mixture was stirred at 100° C. for 1 hr
10. temperatureThe reaction mixture was cooled to room temperature
11. additionwas added to it
12. customThe organic layers were separated
13. dry with materialdried over anhydrous sodium sulfate
14. filtrationfiltered
15. concentrationconcentrated
16. customto obtain a crude product
17. customThis crude product was purified by column chromatography

ORD record

ord-1cebe3aaa0dd4266b8d5cd3ca0e8e0bf

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09447037B2