Hydrochloric Acid → 2-Chloro-3-(piperazin-1-yl)pyrazine

HRID 220544Notes

Reaction equation

HRID 220544 reaction equation
Cl.C(OC([N:9]1[CH2:14][CH2:13][N:12]([C:15]2[C:20]([Cl:21])=[N:19][CH:18]=[CH:17][N:16]=2)[CH2:11][CH2:10]1)=O)(C)(C)C>O1CCOCC1>[Cl:21][C:20]1[C:15]([N:12]2[CH2:11][CH2:10][NH:9][CH2:14][CH2:13]2)=[N:16][CH:17]=[CH:18][N:19]=1

Participants

4

Reactant 2

HCID 313Hydrochloric Acid2×HCID 11150691Tert-butyl 4-(3-chloropyrazin-2-yl)piperazine-1-carboxylate

Product 1

HCID 140864382-Chloro-3-(piperazin-1-yl)pyrazine

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent3×

Procedure

Add 4 M HCl in 1,4-dioxane (10 mL) to 3′-chloro-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-carboxylic acid t-butyl ester (6.80 g, 22.76 mmol). Add 1,4-dioxane (40 mL) and subject the reaction to ultrasound then stir at room temperature under nitrogen for 3 hr. Add further HCl in 1,4-dioxane (40 mL) and stir for 1 hr. Add chloroform (400 mL), wash with 2 N sodium hydroxide (200 mL), saturated aq. sodium chloride (100 mL), dry (magnesium sulfate) and concentrate to give 3′-chloro-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl as a yellow oil which crystallized on standing to give a solid (4.0 g, 88%). MS (ES): m/z=199.1 [M+H]+.

Workup

  1. customthe reaction
  2. stirringstir for 1 hr
  3. washAdd chloroform (400 mL), wash with 2 N sodium hydroxide (200 mL), saturated aq. sodium chloride (100 mL)
  4. dry with materialdry (magnesium sulfate)
  5. concentrationconcentrate

Sources & evidence

ORD record
ord-c8a74cdcd2f44e288f3ebb840c65abcd
Source dataset
uspto-grants-2012_06
Patent number
US08202873B2

Reaction notes

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