Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Hydrazine hydrate (1:1) | HCID 24654 | — |
| Reactant | 2-Hydrazinopyrazine | HCID 1487823 | — |
| Reactant | Ethyl 2-(ethoxymethylene)-4,4,4-trifluoro-3-oxobutanoate | HCID 4685753 | — |
| Reactant | HCID 136284757 | HCID 136284757 | — |
| Solvent | Ethanol | HCID 702 | — |
| Solvent | Acetonitrile | HCID 6342 | — |
| Product | HCID 136356802 | HCID 136356802 | — |
Reaction Steps
To a solution of the title compound from Example 16 Step A (0.500 grams, 2.42 mmol) in ethanol (20 mL) was added hydrazine hydrate (3.25 mL, 35% v/v, 36.3 mmol). The reaction flask was equipped with a reflux condenser, and the reaction mixture was stirred at 80° C. After 12 h, the mixture was allowed to cool to room temperature, whereupon a yellow solid precipitated. The solid was triturated with hexanes, filtered, washed with water, and dried in vacuo: LCMS m/z 203.2 [M+H]+. To a solution of the crude pyrazinyl hydrazine in acetonitrile (10 mL) were added triethylamine (0.675 mL, 4.84 mmol) and ethyl 2-(ethoxymethylene)-4,4,4-trifluoro-3-oxobutyrate (0.872 g, 3.63 mmol). After 40 min at ambient temperature, the reaction mixture was placed in a 60° C. bath and was stirred for 30 min, at which point the reaction mixture was allowed to cool to ambient temperature, then was concentrated in vacuo. Purification by flash chromatography on silica gel (0 to 60% EtOAc in hexanes, then 60 to 100% EtOAc in hexanes) provided the title compound: LCMS m/z 379.1 [M+H]+; 1H NMR (500 MHz, CDCl3) δ 10.98 (s, 1H), 9.35 (s, 1H), 8.85 (s, 1H), 8.23 (s, 1H), 7.93 (dd, J=8.0, 1.5 Hz, 1H), 7.43 (t, J=8.0 Hz, 1H), 7.07 (d, J=8.5 Hz, 1H), 7.04 (t, J=8.0 Hz, 1H).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08455638B2 |
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| Source dataset | uspto-grants-2013_06 |
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| ORD ID | ord-ba8f193f0059420bbbb5d568866b5d47 |
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| Source note | uspto-grants-2013_06 |
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