Lithium Hydroxide → 4-Chloro-5-methyl-1H-pyrrole-2-carboxylic acid

HRID 655763Notes

Reaction equation

HRID 655763 reaction equation
[OH-].[Li+].[Cl:3][C:4]1[CH:5]=[C:6]([C:10]([O:12]CC)=[O:11])[NH:7][C:8]=1[CH3:9]>CO>[Cl:3][C:4]1[CH:5]=[C:6]([C:10]([OH:12])=[O:11])[NH:7][C:8]=1[CH3:9]

Participants

4

Reactant 2

HCID 3939Lithium HydroxideHCID 66707189ethyl 4-chloro-5-methyl-1H-pyrrole-2-carboxylate2×

Product 1

HCID 251376814-Chloro-5-methyl-1H-pyrrole-2-carboxylic acid

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
80 °C

Procedure

Aqueous lithium hydroxide (2 M, 4 ml) was warmed to 50° C. and a solution of ethyl 4-chloro-5-methyl-1H-pyrrole-2-carboxylate (Intermediate 28, 0.30 g, 1.60 mmol) in MeOH was added to it. The reaction was heated to 80° C. and stirred for two hours. The MeOH was removed and the aqueous solution was cooled to 0° C. and acidified with 30% HCl. The precipitated product (0.23 g, 92%) was filtered and dried. MS (ES): 160 (M+1) for C6H6ClNO2; NMR (CDCl3): 2.25 (s, 3H), 6.85 (s, 1H), 8.98 (brs, 1H).

Workup

  1. customThe MeOH was removed
  2. temperaturethe aqueous solution was cooled to 0° C.
  3. filtrationThe precipitated product (0.23 g, 92%) was filtered
  4. customdried

Sources & evidence

ORD record
ord-6e6de01c47904ed383a0e2c331bd643c
Source dataset
uspto-grants-2011_12
Patent number
US08071605B2

Reaction notes

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