| Identification | Back Directory | [Name]
2-CHLORO-3-NITROPYRAZINE | [CAS]
87885-43-6 | [Synonyms]
2-CHLORO-3-NITROPYRAZINE 3-Chloro-2-nitropyrazine Pyrazine, 2-chloro-3-nitro- | [Molecular Formula]
C4H2ClN3O2 | [MDL Number]
MFCD10697796 | [MOL File]
87885-43-6.mol | [Molecular Weight]
159.53 |
| Chemical Properties | Back Directory | [Boiling point ]
283℃ | [density ]
1.600 | [Fp ]
125℃ | [storage temp. ]
under inert gas (nitrogen or Argon) at 2-8°C | [pka]
-5.91±0.10(Predicted) | [Appearance]
Colorless to light yellow Liquid |
| Hazard Information | Back Directory | [Uses]
3-Chloro-2-nitropyrazine is a building block to prepare substituted benzodiazepine calcitonin gene-related peptide (CGRP) receptor antagonists. It is also used to prepare hypoxic cell radiosensitizers. | [Synthesis]
The general procedure for the synthesis of 2-chloro-3-nitropyrazine from the compound (CAS:86536-74-5) was as follows: m-chloroperbenzoic acid (8.0 g, 0.46 mmol, 85%) was dissolved in dichloromethane (100 mL) and cooled to -5 °C. At this temperature, a dichloromethane solution of S,S-dimethyl-N-(2-pyrazinyl)thiimine (5.36 g, 0.028 mmol, dissolved in 30 mL of dichloromethane) was slowly added, and the rate of addition was controlled so that the reaction temperature did not exceed 0 °C, and the addition process lasted for 1 hour. After the addition was completed, the reaction mixture was continued to be stirred at 0 °C for 40 min. Subsequently, a dichloromethane solution of dimethyl sulfide was added at 0 °C and quickly processed to obtain an orange colored clarified solution. The solution was cooled to -78°C and then ozone was passed until the orange solution became colorless. Upon completion of the reaction, the reaction was quenched with sodium dicarbonate solution and then extracted three times with dichloromethane. The organic phases were combined and concentrated to give the crude product. The crude product was purified by fast chromatography to afford 2-chloro-3-nitropyrazine (0.5 g, yield: 7%).1H NMR (DMSO-d6) data were consistent with the structure of the target product. | [References]
[1] Journal of Heterocyclic Chemistry, 1983, vol. 20, # 4, p. 947 - 950 [2] Patent: US2006/47126, 2006, A1. Location in patent: Page/Page column 25 [3] Patent: WO2011/5759, 2011, A2. Location in patent: Page/Page column 69 [4] Patent: WO2013/78254, 2013, A1. Location in patent: Paragraph 00349 |
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