Acetic Acid → 2-[4-(3'-Chloro-2,3,5,6-tetrahydro-[1,2']bipyrazinyl-4-ylmethyl)-pyrazol-1-yl]-ethanol

HRID 220552Notes

Reaction equation

HRID 220552 reaction equation
[Cl:1][C:2]1[C:3]([N:8]2[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]2)=[N:4][CH:5]=[CH:6][N:7]=1.[OH:14][CH2:15][CH2:16][N:17]1[CH:21]=[C:20]([CH:22]=O)[CH:19]=[N:18]1.C(O[BH-](OC(=O)C)OC(=O)C)(=O)C.[Na+].C(O)(=O)C>ClCCCl>[Cl:1][C:2]1[C:3]([N:8]2[CH2:9][CH2:10][N:11]([CH2:22][C:20]3[CH:19]=[N:18][N:17]([CH2:16][CH2:15][OH:14])[CH:21]=3)[CH2:12][CH2:13]2)=[N:4][CH:5]=[CH:6][N:7]=1

Participants

6

Reactant 4

HCID 176Acetic AcidHCID 5049666Sodium triacetoxyborohydrideHCID 140864382-Chloro-3-(piperazin-1-yl)pyrazineHCID 247026081-(2-hydroxyethyl)-1H-pyrazole-4-carbaldehyde

Product 1

HCID 594382452-[4-(3'-Chloro-2,3,5,6-tetrahydro-[1,2']bipyrazinyl-4-ylmethyl)-pyrazol-1-yl]-ethanolYield 90%

Reagents, catalysts & solvents 1

HCID 111,2-DichloroethaneSolvent

Procedure

To a solution of 3′-chloro-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl (0.789 g, 4.01 mmol) and 1-(2-hydroxy-ethyl)-1H-pyrazole-4-carbaldehyde (0.562 g, 4.01 mmol) in 1,2-dichloroethane (35 mL) add sodium triacetoxyborohydride (1.28 g, 6.02 mmol) and acetic acid (0.382 mL) and stir at room temperature for 20 hr. Add saturated aq. sodium bicarbonate, separate the layers, extract the aq. layer twice with DCM, dry (sodium sulfate), filter and concentrate. Purify using silica gel chromatography, eluting with 6:94 methanol (with 2 N ammonia): DCM to give 2-[4-(3′-chloro-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-ylmethyl)-pyrazol-1-yl]-ethanol as a yellow oil (1.16 g, 90%). MS (ES): m/z=323 [M+H]+.

Workup

  1. customAdd saturated aq. sodium bicarbonate, separate the layers
  2. extractionextract the aq. layer twice with DCM
  3. dry with materialdry (sodium sulfate)
  4. filtrationfilter
  5. concentrationconcentrate
  6. customPurify
  7. washeluting with 6:94 methanol (with 2 N ammonia)

Sources & evidence

ORD record
ord-50808a78e9fd40fbadaa865f3674bd71
Source dataset
uspto-grants-2012_06
Patent number
US08202873B2

Reaction notes

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