Water → phenyl(1H-pyrrol-1-yl)acetic acid

15.1 g (0.1 mole) of alpha-phenylglycine were resuspended in 450 ml of dimethylformamide, followed by the addition of 15 g of p-toluene sulphonic acid and 13.2 g (0.1 mole) of 2,5-dimethoxytetrahydrofuran. The mixture was heated to boiling, and at about 95° C. all the solid product was dissolved, the boiling temperature being held for about 60 minutes. After this time, the mixture was cooled, 400 ml of cold water were added and the total mixture was cooled to between 0°-5° C. The mixture was extracted twice with 200 ml of ethyl ether each time, the ether phases being discarded. The aqueous phase was extracted with 500 ml chloroform at pH 1.5. The chloroform extract was treated with 600 ml water and the pH was adjusted to 11. After separating the phases, 500 ml of chloroform were added to the aqueous extract, the pH being adjusted to 1.5 with 2N HCl. The chloroform phase was concentrated to obtain an oil which was crystallised from methanol-water. After drying, the alpha-(N-pyrrolyl)-phenylacetic acid obtained weighed 5.8 g.

1. temperatureThe mixture was heated
2. dissolutionat about 95° C. all the solid product was dissolved
3. temperatureAfter this time, the mixture was cooled
4. temperaturethe total mixture was cooled to between 0°-5° C
5. extractionThe mixture was extracted twice with 200 ml of ethyl ether each time
6. extractionThe aqueous phase was extracted with 500 ml chloroform at pH 1.5
7. extractionThe chloroform extract
8. additionwas treated with 600 ml water
9. customAfter separating the phases, 500 ml of chloroform
10. additionwere added to the aqueous extract
11. concentrationThe chloroform phase was concentrated
12. customto obtain an oil which
13. customwas crystallised from methanol-water
14. customAfter drying

ORD record

ord-e2c05f97a6bf4ce7bebed9d7aea90bce

Source dataset

uspto-grants-1986_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04563477