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

HRID 1845630노트

반응식

HRID 1845630 반응식
Br[C:2]1[CH:3]=[C:4]([C:8]([O:10][CH3:11])=[O:9])[S:5][C:6]=1[CH3:7].C(=O)([O-])[O-].[K+].[K+].[CH3:18][N:19]1[C:23](B2OC(C)(C)C(C)(C)O2)=[CH:22][CH:21]=[N:20]1>O1CCOCC1.O.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>[CH3:7][C:6]1[S:5][C:4]([C:8]([O:10][CH3:11])=[O:9])=[CH:3][C:2]=1[C:23]1[N:19]([CH3:18])[N:20]=[CH:21][CH:22]=1

참가 물질

7

실험 절차

A solution of methyl 4-bromo-5-methyl-2-thiophenecarboxylate (2 g, 8.51 mmol) [prepared in Preparation 10], potassium carbonate (5.88 g, 42.5 mmol), 1-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (2.12 g, 10.21 mmol) [prepared according to Preparation 7] and bis(tri-t-butylphosphine)palladium(0) (0.22 g, 0.43 mmol) in 1,4-Dioxane (35 ml) and H2O (7 ml) was stirred at 80° C. in a sealed tube for 1 h. The reaction mixture 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 and purified via column chromatography (silica, 25% EtOAc in hexanes) affording methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate. This reaction was run in several batches (1 g, 3×2 g) which were combined for workup and purification affording the title compound (5.5 g, 78% combined yield) as a viscous yellow oil: LC-MS (ES) m/e 236 (M+H)+.

후처리

  1. customThe reaction mixture 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. custompurified via column chromatography (silica, 25% EtOAc in hexanes)

출처 및 근거

ORD 기록
ord-b26121d2de254433ab13b8bb7590353b
출처 데이터셋
uspto-grants-2015_02
특허 번호
US08946278B2

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