Potassium Carbonate → methyl 5-ethyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate

HRID 2392043Notes

Reaction equation

Br[C:2]1[CH:3]=[C:4]([C:9]([O:11][CH3:12])=[O:10])[S:5][C:6]=1[CH2:7][CH3:8].C(=O)([O-])[O-].[K+].[K+].[CH3:19][N:20]1[C:24](B2OC(C)(C)C(C)(C)O2)=[CH:23][CH:22]=[N:21]1>CC(C)([P](C(C)(C)C)([Pd][P](C(C)(C)C)(C(C)(C)C)C(C)(C)C)C(C)(C)C)C>[CH2:7]([C:6]1[S:5][C:4]([C:9]([O:11][CH3:12])=[O:10])=[CH:3][C:2]=1[C:24]1[N:20]([CH3:19])[N:21]=[CH:22][CH:23]=1)[CH3:8]

Participants

Conditions

Temperature: 80 °C

Procedure

A solution of methyl 4-bromo-5-ethyl-2-thiophenecarboxylate (300 mg, 1.204 mmol), potassium carbonate (832 mg, 6.02 mmol), 1-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (326 mg, 1.565 mmol)[prepared according to Preparation 7] and bis(tri-t-butylphosphine)palladium(0) (30.8 mg, 0.060 mmol) were combined in a sealed tube and stirred at 80° C. for 1 h. The reaction contents were then partitioned between H2O-DCM and the aqueous phase was washed several times with DCM. The combined organic fractions were dried over Na2SO4 and concentrated affording methyl 5-ethyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate (301 mg, 1.204 mmol, 100% yield) as a brown oil: LCMS (ES) m/e 251 (M+H)+.

Workup

customThe reaction contents
customwere then partitioned between H2O-DCM
washthe aqueous phase was washed several times with DCM
dry with materialThe combined organic fractions were dried over Na2SO4
concentrationconcentrated

Sources & evidence

ORD record: ord-34a8aa3e9f6c403297239fb3e2cb7bbe
Source dataset: uspto-grants-2012_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08273782B2

Reaction notes

Loading…