N-bromobutanimide → methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylate

HRID 1845453Notes

Reaction equation

HRID 1845453 reaction equation
[CH3:1][C:2]1[S:6][C:5]([C:7]([O:9][CH3:10])=[O:8])=[CH:4][C:3]=1[C:11]1[N:15]([CH3:16])[N:14]=[CH:13][CH:12]=1.C1C(=O)N([Br:24])C(=O)C1>O1CCCC1>[Br:24][C:12]1[CH:13]=[N:14][N:15]([CH3:16])[C:11]=1[C:3]1[CH:4]=[C:5]([C:7]([O:9][CH3:10])=[O:8])[S:6][C:2]=1[CH3:1]

Participants

4

Procedure

A solution of methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate (580 mg, 2.45 mmol) and n-bromosuccinimide (437 mg, 2.45 mmol) in tetrahydrofuran (12.300 ml) was stirred in a sealed tube for 1 h at 70° C. The solution was then partitioned between H2O-DCM and the aqueous phase was washed several times with DCM. The combined organic fractions were dried over Na2SO4, concentrated then purified via column chromatography (silica, 20% EtOAc in hexanes) yielding methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylate (600 mg, 1.90 mmol, 78° A yield) as a yellow oil: LCMS (ES) m/e 314, 316 (M, M+H)+.

Workup

  1. customThe solution was then partitioned between H2O-DCM
  2. washthe aqueous phase was washed several times with DCM
  3. dry with materialThe combined organic fractions were dried over Na2SO4
  4. concentrationconcentrated
  5. customthen purified via column chromatography (silica, 20% EtOAc in hexanes)

Sources & evidence

ORD record
ord-759615f8320f4fc5a5bf4594ff98a5cf
Source dataset
uspto-grants-2015_02
Patent number
US08946278B2

Reaction notes

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