Triethylamine → 6-Phenylethynyl-pyrazolo[1,5-a]pyrimidine

HRID 1426185Notes

Reaction equation

Br[C:2]1[CH:3]=[N:4][C:5]2[N:6]([N:8]=[CH:9][CH:10]=2)[CH:7]=1.[C:11]1([C:17]#[CH:18])[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.C(N(CC)CC)C.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>C1COCC1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.Cl[Pd]Cl.[Cu]I>[C:11]1([C:17]#[C:18][C:2]2[CH:3]=[N:4][C:5]3[N:6]([N:8]=[CH:9][CH:10]=3)[CH:7]=2)[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1

Participants

Conditions

Temperature: 65 °C

Procedure

Bis-(triphenylphosphine)-palladium(II)dichloride (27 mg, 0.04 mmol) was dissolved in 1 ml of THF. 6-Bromo-pyrazolo[1,5-a]pyrimidine (150 mg, 0.76 mmol) and phenylacetylene (130 μl, 1.21 mmol) were added at room temperature. Triethylamine (310 μl, 2.3 mmol), triphenylphosphine (6 mg, 0.023 mmol) and copper(I) iodide (4 mg, 0.023 mmol) were added and the mixture was stirred for 2 hours at 65° C. The reaction mixture was cooled and extracted with saturated NaHCO3 solution and two times with a small volume of dichloromethane. The crude product was purified by flash chromatography by directly loading the dichloromethane layers onto a silica gel column and eluting with heptane:ethyl acetate 100:0→50:50. The desired compound was obtained as a yellow solid (150 mg, 90% yield), MS: m/e=220.3 (M+H+).

Workup

temperatureThe reaction mixture was cooled
extractionextracted with saturated NaHCO3 solution and two times with a small volume of dichloromethane
customThe crude product was purified by flash chromatography
washeluting with heptane:ethyl acetate 100:0→50:50

Sources & evidence

ORD record: ord-f52c96a01c1448289d0a79c11bc60808
Source dataset: uspto-grants-2015_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08933094B2

Reaction notes

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