Hydrochloric Acid → 3'-chloro-3,4,5,6-tetrahydro-2H-[1,2']bipyrazinyl dihydrochloride

Reaction equation

C(OC([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[C:19]([Cl:20])=[N:18][CH:17]=[CH:16][N:15]=2)[CH2:10][CH2:9]1)=O)(C)(C)C.[ClH:21].O1CCOCC1>>[ClH:20].[ClH:21].[Cl:20][C:19]1[C:14]([N:11]2[CH2:10][CH2:9][NH:8][CH2:13][CH2:12]2)=[N:15][CH:16]=[CH:17][N:18]=1

Participants

Reactant 3

HCID 313Hydrochloric Acid

HCID 312751,4-Dioxane

HCID 11150691Tert-butyl 4-(3-chloropyrazin-2-yl)piperazine-1-carboxylate

Product 1

HCID 866416583'-chloro-3,4,5,6-tetrahydro-2H-[1,2']bipyrazinyl dihydrochlorideYield 78%

Procedure

To 3′-chloro-2,3,5,6-tetrahydro-[1,2′]bipyrazinyl-4-carboxylic acid t-butyl ester (3.00 g, 10.0 mmol, 1 eq) add a 4 M solution of hydrochloric acid in 1,4-dioxane (100 mL, 400 mmol, 40 eq) and stir at room temperature for 3 hr. Filter precipitate and wash with diethyl ether. Dry the powder in vacuum oven over night to give 3′-chloro-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl dihydrochloride as a pale yellow powder (2.11 g, 78%). MS (ES): m/z=199 [M+H]+.