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

HRID 2042136Notes

Reaction equation

HRID 2042136 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.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[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

8

Reactant 4

HCID 8471TriethylamineHCID 10821PhenylacetyleneHCID 11776TriphenylphosphineHCID 222367016-Bromopyrazolo[1,5-a]pyrimidine

Product 1

HCID 509149146-Phenylethynyl-pyrazolo[1,5-a]pyrimidine

Reagents, catalysts & solvents 3

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)CatalystHCID 178418476HCID 178418476, compoundCatalystHCID 8028TetrahydrofuranSolvent

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

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

Sources & evidence

ORD record
ord-b3466dee2c2245f7bf133fe4831f714d
Source dataset
uspto-grants-2013_11
Patent number
US08586581B2

Reaction notes

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