Toluene → 3-(2,5-dimethyl-1H-pyrrol-1-yl)benzoic acid

HRID 1759205Notes

Reaction equation

HRID 1759205 reaction equation
[NH2:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([OH:7])=[O:6].[CH2:11]([CH2:15][C:16](=O)[CH3:17])[C:12]([CH3:14])=O.C1(C)C=CC=CC=1>C1(C)C=CC(S(O)(=O)=O)=CC=1.O>[CH3:17][C:16]1[N:1]([C:2]2[CH:3]=[C:4]([CH:8]=[CH:9][CH:10]=2)[C:5]([OH:7])=[O:6])[C:12]([CH3:14])=[CH:11][CH:15]=1

Participants

6

Reactant 3

HCID 1140TolueneHCID 74193-Aminobenzoic AcidHCID 80352,5-Hexanedione

Product 1

HCID 2133293-(2,5-dimethyl-1H-pyrrol-1-yl)benzoic acidYield 89.7%

Reagents, catalysts & solvents 2

HCID 6101p-Toluenesulfonic acidCatalystHCID 962WaterSolvent

Procedure

In a reaction vessel equipped with a Dean-Stark trap was placed 13.7 grams (0.10 mole) of 3-aminobenzoic acid, 11.4 grams (0.10 mole) of acetonylacetone, 0.10 gram of p-toluenesulfonic acid and 150 ml of toluene. The stirred reaction mixture was heated under reflux for 15.5 hours during which time the theoretical amount of by-product water was collected in the Dean-Stark trap. The reaction mixture was cooled and placed in a separatory funnel where it was washed with two portions of 50 ml each of aqueous 2N sodium hydroxide. The combined base washes were backwashed with 50 ml of toluene then acidified with aqueous 2 N hydrochloric acid. A solid precipitate was collected by filtration and recrystallized from heptane to give 19.3 grams of 3-(2,5-dimethylpyrrol-1-yl)benzoic acid; mp 148°-150° C.

Workup

  1. customIn a reaction vessel equipped with a Dean-Stark trap
  2. customThe stirred reaction mixture
  3. temperaturewas heated
  4. customwas collected in the Dean-Stark trap
  5. temperatureThe reaction mixture was cooled
  6. customplaced in a separatory funnel
  7. washwhere it was washed with two portions of 50 ml each of aqueous 2N sodium hydroxide
  8. filtrationA solid precipitate was collected by filtration
  9. customrecrystallized from heptane

Sources & evidence

ORD record
ord-0196707a52ba41a0b2f07ba50f84f753
Source dataset
uspto-grants-1982_07
Patent number
US04339457

Reaction notes

Loading…