Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Hydrochloric Acid | HCID 313 | — |
| Reactant | Hydrazine | HCID 9321 | — |
| Reactant | 2,2,6,6-Tetramethylpiperidine | HCID 13035 | — |
| Reactant | 6-Bromonicotinic acid | HCID 238932 | — |
| Reactant | Butyllithium | HCID 178418339 | — |
| Solvent | Dimethylformamide | HCID 6228 | — |
| Solvent | Tetrahydrofuran | HCID 8028 | — |
| Product | HCID 77230264 | HCID 77230264 | 12% |
Reaction Steps
2,2,6,6-Tetramethylpiperidine (9.58 mL, 56.4 mmol) was dissolved in dry THF (100 mL), and cooled to 0° C., whilst n-butyllithium (1.6M in hexanes, 35.2 mL, 56.43 mmol) was added over 15 min. The resulting solution was cooled to −78° C., and 6-bromonicotinic acid (3.8 g, 18.8 mmol.) was added as a solid in four equal portions, with stirring over 10 min. Stirring was continued at this temperature for 1.5 h, and the resulting deep-red solution was treated with dry DMF (10 mL) and allowed to warm to room temperature overnight. The mixture was poured onto water (200 mL) and acidified with 1M HCl, and the aqueous phase was extracted with EtOAc (×4). The combined organic phases were washed (brine), dried (sodium sulfate) and concentrated to give a yellow oil, which was dissolved in THF (25 mL) and treated with hydrazine (1M in THF, 19 mL). The precipitate was filtered, and dissolved in ethanol (50 mL) and heated to reflux in the presence of potassium acetate (5 g). The mixture was concentrated under reduced pressure and the brown oily solid was triturated with diethyl ether and the ethereal solution was subjected to flash chromatography (50% ethyl acetate/isohexane) to give a white solid (0.5 g, 12%). 1H NMR (400 MHz) DMSO-d6 δ: 8.21 (1H, s), 8.36 (1H, s), 9.20 (1H, s), 13.09, (1H, s). MS (ES M+1) 226/228.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07329659B2 |
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| Source dataset | uspto-grants-2008_02 |
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| ORD ID | ord-9d7edc3bbf9a4161854d8c841e619fed |
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| Source note | uspto-grants-2008_02 |
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