Potassium Carbonate → Tert-butyl 4-(5-chloropyrazin-2-YL)piperazine-1-carboxylate

HRID 459868Notes

Reaction equation

CN1C(=O)CCC1.Cl[C:9]1[CH:14]=[N:13][C:12]([Cl:15])=[CH:11][N:10]=1.[C:16]([O:20][C:21]([N:23]1[CH2:28][CH2:27][NH:26][CH2:25][CH2:24]1)=[O:22])([CH3:19])([CH3:18])[CH3:17].C(=O)([O-])[O-].[K+].[K+]>O>[Cl:15][C:12]1[CH:11]=[N:10][C:9]([N:26]2[CH2:25][CH2:24][N:23]([C:21]([O:20][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:22])[CH2:28][CH2:27]2)=[CH:14][N:13]=1

Participants

Conditions

Temperature: 100 °C

Procedure

To an NMP (7.5 ml) solution of 1.51 g of 2,5-dichloropyrazine were added 2.00 g of 1-(t-butoxycarbonyl)piperazine and 2.00 g of potassium carbonate, followed by 1 hour of stirring under heating at 100° C. The mixture was cooled to room temperature, and water was added thereto, followed by extraction with ethyl acetate. The organic layer was washed with water and brine and then dried over anhydrous magnesium sulfate, and thereafter, the solvent was evaporated. The residue was purified by silica gel column chromatography (chloroform-methanol) to obtain 2.73 g of 2-chloro-5-(4-t-butoxycarbonylpiperazin-1-yl)pyrazine. Using this compound, 2-chloro-5-{4-[6-(3,4-dimethoxyphenyl)pyridine-2-carbonyl]piperazin-1-yl}pyrazine was obtained in a similar manner to Example 14 as colorless crystals.

Workup

temperatureThe mixture was cooled to room temperature
extractionfollowed by extraction with ethyl acetate
washThe organic layer was washed with water and brine
dry with materialdried over anhydrous magnesium sulfate
customthe solvent was evaporated
customThe residue was purified by silica gel column chromatography (chloroform-methanol)

Sources & evidence

ORD record: ord-1c01d216e0cd42eabb9a1cc79af91373
Source dataset: uspto-grants-2007_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07196080B2

Reaction notes

Loading…