Sodium Carbonate → Ethyl 7-aminothieno[2,3-b]pyrazine-6-carboxylate

HRID 1184817Notes

Reaction equation

HRID 1184817 reaction equation
Cl[C:2]1[C:3]([C:8]#[N:9])=[N:4][CH:5]=[CH:6][N:7]=1.C(=O)([O-])[O-].[Na+].[Na+].[CH2:16]([O:18][C:19](=[O:22])[CH2:20][SH:21])[CH3:17]>C(O)C>[NH2:9][C:8]1[C:3]2[C:2](=[N:7][CH:6]=[CH:5][N:4]=2)[S:21][C:20]=1[C:19]([O:18][CH2:16][CH3:17])=[O:22]

Participants

5

Reactant 3

HCID 10340Sodium CarbonateHCID 12185Ethyl ThioglycolateHCID 2924653-Chloropyrazine-2-carbonitrile

Product 1

HCID 2820821Ethyl 7-aminothieno[2,3-b]pyrazine-6-carboxylateYield 68.6%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of 3-chloropyrazine-2-carbonitrile (17.9 g, 128 mmol), sodium carbonate (17.7 g, 167 mmol) and ethyl-2-mercaptoacetate (18.4 mL, 167 mmol) in ethanol (120 mL) was heated to reflux for 4.5 h. Quenched with water (1.5 L) and stirred for 30 min. The resulting precipitate was collected and washed with water. The residue was dissolved in diethyl ether and a black precipitate was filtrated off. Ether was evaporated to give pure compound ethyl 7-aminothieno[2,3-b]pyrazine-6-carboxylate 7 (19.6 g, 68.5%). 1H-NMR (400 MHz, CDCl3) 1.42 (t, J=7.2 Hz, 3H), 4.40 (q, J=7.2 Hz, 2H), 6.19 (br s, 1H), 8.58 (d, J=2.2 Hz, 1H), 8.63 (d, J=2.2 Hz, 1H).

Workup

  1. temperaturewas heated
  2. temperatureto reflux for 4.5 h
  3. customQuenched with water (1.5 L)
  4. customThe resulting precipitate was collected
  5. washwashed with water
  6. dissolutionThe residue was dissolved in diethyl ether
  7. filtrationa black precipitate was filtrated off
  8. customEther was evaporated

Sources & evidence

ORD record
ord-d6aa3e1b4e374f28ba77786de6b250da
Source dataset
uspto-grants-2014_03
Patent number
US08669256B2

Reaction notes

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