Dimethylformamide → HCID 86602426, compound

Temperature

0 °C

To 3.15 ml (41 mmol) of DMF at 0° C. under argon was added dropwise 3.81 ml (41 mmol) of phosphorus oxychloride. The cooling bath was removed and stirring was continued for 15 min. The solution was diluted with 9 ml of 1,2-dichloroethane and again cooled to 0° C. A solution of 3.0 g (37 mmol) of 3-methylpyrrole in 9 ml of 1,2-dichloroethane was added dropwise. The mixture was heated to reflux for 15 min, cooled to 0° C. and a solution of 16.2 g (203 mmol) of sodium acetate in 45 ml of water was added with vigorous stirring. The mixture was heated at reflux for 20 min and allowed to cool to room temperature. The aqueous layer was separated and extracted twice with methylene chloride. The combined organic layers were washed with sat NaHCO3 until pH 7, dried (MgSO4), and the solvent removed to yield a dark oily solid which was purified by flash chromatography (10% EtOAc:hexane) to afford 3.6 g (89%) of a 4:1 mixture of 2-formyl-3-methylpyrrole and 2-formyl-4-methylpyrrole as a pale yellow solid.

1. customThe cooling bath was removed
2. additionThe solution was diluted with 9 ml of 1,2-dichloroethane
3. temperatureThe mixture was heated
4. temperatureto reflux for 15 min
5. temperaturecooled to 0° C.
6. temperatureThe mixture was heated
7. temperatureat reflux for 20 min
8. temperatureto cool to room temperature
9. customThe aqueous layer was separated
10. extractionextracted twice with methylene chloride
11. washThe combined organic layers were washed with sat NaHCO3 until pH 7
12. dry with materialdried (MgSO4)
13. customthe solvent removed
14. customto yield a dark oily solid which
15. customwas purified by flash chromatography (10% EtOAc:hexane)
16. customto afford

ORD record

ord-3ce5ba08451140319de820ef393f8bfd

Source dataset

uspto-grants-2006_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06982265B1