Sodium Hydroxide → 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-chloro-2-thiophenecarboxylic acid

HRID 1961265Notes

Reaction equation

HRID 1961265 reaction equation
[Cl:1][C:2]1[S:6][C:5]([C:7]([O:9]C)=[O:8])=[CH:4][C:3]=1[C:11]1[N:15]([CH3:16])[N:14]=[CH:13][CH:12]=1.[Br:17]N1C(=O)CCC1=O.[OH-].[Na+]>C1COCC1>[Br:17][C:12]1[CH:13]=[N:14][N:15]([CH3:16])[C:11]=1[C:3]1[CH:4]=[C:5]([C:7]([OH:9])=[O:8])[S:6][C:2]=1[Cl:1]

Participants

5

Reactant 3

HCID 14798Sodium HydroxideHCID 67184N-bromobutanimideHCID 57826577Methyl 5-chloro-4-(1-methyl-1H-pyrazol-5-yl)thiophene-2-carboxylate

Product 1

HCID 578264444-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-chloro-2-thiophenecarboxylic acidYield 28%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
70 °C

Procedure

To a solution of methyl 5-chloro-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate (300 mg, 1.169 mmol)[prepared according to the procedure of Example 193] in THF (10 ml) was added N-bromosuccinimide (212 mg, 1.19 mmol). The mixture was sealed and heated at 70° C. After 2 h, a solution of 6N NaOH (2.0 ml, 6.0 M, 11.84 mmol) was added in one portion. The resulting mixture stirred for an additional 2 h and was partitioned between DCM-H2O. The pH of the aqueous phase was adjusted to ˜3 and extracted several times with DCM. The combined organic fractions were dried over Na2SO4, concentrated affording the title compound as a colorless oil (105 mg, 28%): LC-MS (ES) m/z=322 (M+H)+.

Workup

  1. customThe mixture was sealed
  2. customwas partitioned between DCM-H2O
  3. extractionextracted several times with DCM
  4. dry with materialThe combined organic fractions were dried over Na2SO4
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-e7898a42b9b34b2bb49004388135d897
Source dataset
uspto-grants-2013_04
Patent number
US08410158B2

Reaction notes

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