Potassium Carbonate → 5-(1-methyl-1H-pyrazol-5-yl)thiophene-2-carboxylic acid

HRID 2391967Notes

Reaction equation

Br[C:2]1[S:6][C:5]([C:7]([OH:9])=[O:8])=[CH:4][CH:3]=1.C([O-])([O-])=O.[K+].[K+].CC1(C)COB([C:23]2[N:27]([CH3:28])[N:26]=[CH:25][CH:24]=2)OC1>O1CCOCC1.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[CH3:28][N:27]1[C:23]([C:2]2[S:6][C:5]([C:7]([OH:9])=[O:8])=[CH:4][CH:3]=2)=[CH:24][CH:25]=[N:26]1

Participants

Conditions

Temperature: 80 °C

Procedure

To a solution of 5-bromo-2-thiophenecarboxylic acid (100 mg, 0.48 mmol) in dioxane/H2O (5:1, 6 mL) was added K2CO3 (267 mg, 1.93 mmol), tetrakistriphenylphosphine Pd(0) (28 mg, 24 umol) and 5-(5,5-dimethyl-1,3,2-dioxaborinane-2-yl)-1-methyl-1H-pyrazole (94 mg, 0.48 mmol). The reaction mixture was heated to 80° C. in a sealed tube for 12 h and was then partitioned between 6N NaOH and DCM. The pH of the aqueous phase was adjusted to ˜3 with 3M HCl and washed several times with DCM. The combined organic fractions were dried (Na2SO4), concentrated under vacuum and used directly without further purification (˜100 mg, quant.): LC-MS (ES) m/z=209 (M+H)+.

Workup

customwas then partitioned between 6N NaOH and DCM
washwashed several times with DCM
dry with materialThe combined organic fractions were dried (Na2SO4)
concentrationconcentrated under vacuum
customused directly without further purification (˜100 mg, quant.)

Sources & evidence

ORD record: ord-fb5dec2525164ca9a8663e5c49fa7af4
Source dataset: uspto-grants-2012_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08273782B2

Reaction notes

Loading…