Water → Ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate

HRID 925585Notes

Reaction equation

HRID 925585 reaction equation
[NH2:1][C:2]1[C:7]([Br:8])=[N:6][C:5]([Br:9])=[CH:4][N:3]=1.Br[CH2:11][C:12](=O)[C:13]([O:15][CH2:16][CH3:17])=[O:14].O.C(Cl)Cl>COC(=O)OC>[Br:9][C:5]1[N:6]=[C:7]([Br:8])[C:2]2[N:3]([CH:11]=[C:12]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[N:1]=2)[CH:4]=1

Participants

6

Reactant 4

HCID 962WaterHCID 6344DichloromethaneHCID 66144Ethyl bromopyruvateHCID 6200042-Amino-3,5-dibromopyrazine

Product 1

HCID 19827087Ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylateYield 50.6%

Reagents, catalysts & solvents 1

HCID 12021Dimethyl CarbonateSolvent

Conditions

Temperature
110 °C

Procedure

To a stirred solution of 2-amino-3,5-dibrompyrazine (20 g, 79 mmol) in dimethylcarbonate (133 mL) at rt was added ethyl 3-bromo-2-oxopropanoate (17.14 g, 79 mmol) in one portion. After stirring at 110° C. for 3 h, the solution was stirred at rt overnight. Water and DCM were added and the aqueous phase was extracted with DCM. After washing of the organic phase with water, drying over Na2(SO4) and filtration the organic phase was evaporated. Flash chromatography yielded 13.95 g (50.6%) ethyl 6,8-dibromoimidazo[1,2-a]pyrazine-2-carboxylate: 1H-NMR (300 MHz, CDCl3): δ=8.30 (s, 1H), 8.27 (s, 1H), 4.48 (q, 2H), 1.43 (tr, 3H) ppm.

Workup

  1. stirringthe solution was stirred at rt overnight
  2. extractionthe aqueous phase was extracted with DCM
  3. washAfter washing of the organic phase with water
  4. dry with materialdrying over Na2(SO4) and filtration the organic phase
  5. customwas evaporated

Sources & evidence

ORD record
ord-7d7c2fdf99af41b09c37c23d3203adb5
Source dataset
uspto-grants-2016_03
Patent number
US09284317B2

Reaction notes

Loading…