Identification | Back Directory | [Name]
5-METHOXYPYRAZINE-2-CARBOXYLIC ACID | [CAS]
40155-42-8 | [Synonyms]
5-Methoxypyrazine-2-carboxylic 5-Methoxy-pyrazinecarboxylic acid 5-METHOXYPYRAZINE-2-CARBOXYLIC ACID Pyrazinecarboxylic acid, 5-methoxy- 2-Pyrazinecarboxylicacid, 5-Methoxy- 5-Methoxypyrazine-2-carboxylic acid 95% 2-Carboxy-5-methoxypyrazine, 2-Carboxy-5-methoxy-1,4-diazine | [Molecular Formula]
C6H6N2O3 | [MDL Number]
MFCD10697773 | [MOL File]
40155-42-8.mol | [Molecular Weight]
154.12 |
Chemical Properties | Back Directory | [Melting point ]
197.5-199.5℃ | [Boiling point ]
296.8±35.0 °C(Predicted) | [density ]
1.371±0.06 g/cm3(Predicted) | [storage temp. ]
Sealed in dry,2-8°C | [form ]
Solid | [pka]
3.18±0.10(Predicted) | [color ]
Light yellow to Brown to Dark green | [InChI]
InChI=1S/C6H6N2O3/c1-11-5-3-7-4(2-8-5)6(9)10/h2-3H,1H3,(H,9,10) | [InChIKey]
YVGVOPNUEFTVQO-UHFFFAOYSA-N | [SMILES]
C1(C(O)=O)=NC=C(OC)N=C1 |
Hazard Information | Back Directory | [Synthesis]
Step 2: Preparation of 5-methoxypyrazine-2-carboxylic acid
To a solution of 5-chloropyrazine-2-carboxylic acid (7 g, 44.15 mmol) in methanol (55 mL) was added concentrated sulfuric acid (0.4 mL) and heated to reflux for 4 hours at 65 °C. Upon completion of the reaction, the reaction mixture was cooled to room temperature and diluted with methanol (15 mL). Subsequently, a methanolic solution of sodium methanolate (8.58 g, 158.94 mmol, 35 mL) was slowly added and the reaction mixture was stirred for 30 min at room temperature. Next, a 30 mL aqueous solution of sodium hydroxide (2.825 g, 70.643 mmol) was added to the reaction mixture, followed by 40 mL of water. The reaction mixture was heated at 40 °C for 1 h, followed by concentration under reduced pressure to remove methanol. The residue was diluted with water and the pH was adjusted to 2-3 with 38% aqueous hydrochloric acid and then extracted with ethyl acetate (600 mL x 3). The organic layers were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give 5-methoxypyrazine-2-carboxylic acid (6.43 g, 94% yield) as an orange solid. Mass spectrometry analysis: calculated value [M + H]+: 155.04; measured value [M + H]+: 155.1. | [References]
[1] Patent: WO2015/48507, 2015, A1. Location in patent: Paragraph 0171 |
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