Triethylamine → 2-(Benzyloxy)-5-[(4-fluorophenyl)carbonyl]-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine

HRID 571730Notes

Reaction equation

HRID 571730 reaction equation
[F:1][C:2]1[CH:10]=[CH:9][C:5]([C:6](Cl)=[O:7])=[CH:4][CH:3]=1.[CH2:11]([O:18][C:19]1[CH:27]=[C:22]2[CH2:23][NH:24][CH2:25][CH2:26][N:21]2[N:20]=1)[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.C(N(CC)CC)C>C(Cl)Cl.C([O-])([O-])=O.[Na+].[Na+]>[CH2:11]([O:18][C:19]1[CH:27]=[C:22]2[CH2:23][N:24]([C:6]([C:5]3[CH:9]=[CH:10][C:2]([F:1])=[CH:3][CH:4]=3)=[O:7])[CH2:25][CH2:26][N:21]2[N:20]=1)[C:12]1[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=1

Participants

6

Reactant 3

HCID 8471TriethylamineHCID 678794-Fluorobenzoyl chlorideHCID 867064922-(Benzyloxy)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine

Product 1

HCID 725512832-(Benzyloxy)-5-[(4-fluorophenyl)carbonyl]-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazineYield 83%

Reagents, catalysts & solvents 2

HCID 6344DichloromethaneSolventHCID 10340Sodium CarbonateSolvent

Procedure

4-Fluorobenzoyl chloride (0.36 mL, 3.04 mmol) was added to a stirred solution of 2-(benzyloxy)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine (0.71 g, 2.53 mmol) and triethylamine (0.65 mL, 3.8 mmol) in DCM (25 mL) under nitrogen at 0° C. The mixture was stirred at room temperature for 16 hours, diluted with a saturated solution of Na2CO3 and extracted with DCM. The organic layer was separated, dried (Na2SO4), filtered and the solvents evaporated in vacuo. The crude product was purified by flash column chromatography (silica; AcOEt in DCM 0/100 to 20/80). The desired fractions were collected, the solvents evaporated in vacuo and the residue triturated with DIPE to yield 2-(benzyloxy)-5-[(4-fluorophenyl)carbonyl]-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine (0.73 g, 83% yield) as a white solid. C20H18FN3O2. 1H NMR (400 MHz, CDCl3) δ ppm 4.10 (br. s., 4H), 4.73 (br. s., 2 H), 5.18 (s, 2 H), 5.50 (br. s., 1 H), 7.10-7.19 (m, 2 H), 7.29-7.35 (m, 1 H), 7.35-7.41 (m, 2 H), 7.41-7.46 (m, 2 H), 7.46-7.51 (m, 2 H).

Workup

  1. extractionextracted with DCM
  2. customThe organic layer was separated
  3. dry with materialdried (Na2SO4)
  4. filtrationfiltered
  5. customthe solvents evaporated in vacuo
  6. customThe crude product was purified by flash column chromatography (silica; AcOEt in DCM 0/100 to 20/80)
  7. customThe desired fractions were collected
  8. customthe solvents evaporated in vacuo
  9. customthe residue triturated with DIPE

Sources & evidence

ORD record
ord-0dbd249fa9bd48bb876d7eb4b253d53d
Source dataset
uspto-grants-2015_05
Patent number
US09029366B2

Reaction notes

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