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

HRID 2392178Notes

Reaction equation

HRID 2392178 reaction equation
C1C(=O)N([Br:8])C(=O)C1.[CH3:9][C:10]1[S:14][C:13]([C:15]([O:17][CH3:18])=[O:16])=[CH:12][C:11]=1[C:19]1[N:23]([CH3:24])[N:22]=[CH:21][CH:20]=1>O1CCCC1>[Br:8][C:20]1[CH:21]=[N:22][N:23]([CH3:24])[C:19]=1[C:11]1[CH:12]=[C:13]([C:15]([O:17][CH3:18])=[O:16])[S:14][C:10]=1[CH3:9]

Participants

4

Reactant 2

HCID 67184N-bromobutanimideHCID 57826485methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate

Product 1

HCID 57826393methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylateYield 92%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
70 °C

Procedure

NBS (2.03 g, 11.41 mmol) was added in portions to a 75 mL sealed tube reactor containing methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate (2.1 g, 8.89 mmol) [prepared according to the procedure of Preparation 10] in Tetrahydrofuran (THF) (40 ml) at room temperature. The mixture was heated to 70° C. for 1 hour. The reaction mixture was partitioned between CHCl3 and H2O, the organic layer dried with Na2SO4, the reaction mixture adsorbed onto silica and purified via column chromatography (15-40% EtOAc/Hex) affording the title compound (2.57 g, 8.15 mmol, 92%): LC-MS (ES) m/z=316 (M+H)+.

Workup

  1. customsealed tube reactor
  2. customprepared
  3. customThe reaction mixture was partitioned between CHCl3 and H2O
  4. dry with materialthe organic layer dried with Na2SO4
  5. custompurified via column chromatography (15-40% EtOAc/Hex)

Sources & evidence

ORD record
ord-fe5860c10df54c0497c9bc2beb4e2f4e
Source dataset
uspto-grants-2012_09
Patent number
US08273782B2

Reaction notes

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