HCID 291759, compound → 3-(4-Methyl-1H-pyrrol-3-yl)propanoic acid

Temperature

10 °C

2-Carboxy-5-ethoxycarbonyl-3-(2-ethoxycarbonylethyl)-4-methylpyrrole (50.5 g) and 400 mL of 10% sodium hydroxide solution was heated to 180° C. in a Parr autoclave for 90 min. This process was repeated 4 more times on a total of 252.5 g of 2-carboxy-5-ethoxycarbonyl-3-(2-ethoxycarbonylethyl)-4-methylpyrrole. The five solutions were combined and rotary evaporated to a volume of about 1.8 L of thick black residue. The mixture was cooled to 10° C. in a water bath, and 50% sulfuric acid was slowly added until the pH was 2, keeping the temperature <20° C. Ethyl ether (1400 mL) was added and the mixture filtered, saving the precipitate. The precipitate was extracted in a Soxhlet apparatus with 500 mL of ether. The combined ether layers were washed with 250 mL, and then 150 mL, of water, and the water layers back extracted with 150 mL of ether. All the ether layers were rotary evaporated and the residue dried to give 123.5 g of 3-(2-carboxyethyl)-4-methylpyrrole.

1. customrotary evaporated to a volume of about 1.8 L of thick black residue
2. addition50% sulfuric acid was slowly added until the pH was 2
3. customthe temperature <20° C
4. additionEthyl ether (1400 mL) was added
5. filtrationthe mixture filtered
6. extractionThe precipitate was extracted in a Soxhlet apparatus with 500 mL of ether
7. washThe combined ether layers were washed with 250 mL
8. extraction150 mL, of water, and the water layers back extracted with 150 mL of ether
9. customAll the ether layers were rotary evaporated
10. customthe residue dried

ORD record

ord-a064bdc02121427eaed20d274152cf16

Source dataset

uspto-grants-2005_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06846839B1