Ethanol → 2,3,4,5-Tetraiodopyrrol-1-acetic acid

To a solution of 22.9 g of compound A), 2,3,4,5-tetraiodopyrrole (40.13 mmol), in 170 mL of DMF, 16.05 mL of 2.5 M MeONa in MeOH (40.13 mmol) are added under stirring for 15 min in nitrogen atmosphere. MeOH is removed under reduced pressure and 10 g of ethyl iodoacetate (product instantly prepared from BrCH2COOEt and 4 KI equivalents in acetone) (46.73 mmol) are dropwise added (30 min) to the residue. The solution is kept at room temperature for 1.5 h. After dilution with H2O, an intensely coloured solid precipitates, then is filtered, redissolved in DMF and treated with carbon Carbopuron 4N. The solution is filtered, concentrated to dryness and crystallized from abs. EtOH, to obtain 20 g of 2,3,4,5-tetraiodopyrrol-l-acetic acid (30.45 mmol) ethyl ester.

1. customMeOH is removed under reduced pressure and 10 g of ethyl iodoacetate (product
2. custominstantly prepared from BrCH2COOEt and 4 KI equivalents in acetone) (46.73 mmol)
3. additionare dropwise added (30 min) to the residue
4. waitThe solution is kept at room temperature for 1.5 h
5. customAfter dilution with H2O, an intensely coloured solid precipitates
6. filtrationis filtered
7. dissolutionredissolved in DMF
8. additiontreated with carbon Carbopuron 4N
9. filtrationThe solution is filtered
10. concentrationconcentrated to dryness
11. customcrystallized from abs

ORD record

ord-1a2e5828e3d64c898c4ad16d1cbe441e

Source dataset

uspto-grants-1996_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05587487