Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Hydrazine | HCID 9321 | — |
| Reactant | 3-Methyl-2-butanone | HCID 11251 | — |
| Reactant | 2,5-Dibromopyridine | HCID 69353 | — |
| Reactant | 2-Hydrazinopyridine | HCID 78645 | — |
| Reactant | 5-Bromo-2-hydrazinopyridine | HCID 11535699 | — |
| Solvent | Benzene | HCID 241 | — |
| Solvent | 2-Methoxyethanol | HCID 8019 | — |
| Product | HCID 11241897 | HCID 11241897 | — |
Reaction Steps
To 40 g of 2,5-dibromopyridine in 200 mL of 2-methoxyethanol is added 53 mL of anhydrous hydrazine and the mixture is heated at 110° C. for 3 hours to generate the 5-bromo-2-hydrazinopyridine. A mixture of 10 g of this hydrazinopyridine is heated at reflux overnight with 11 mL of 3-methyl-2-butanone in 40 mL of benzene equipped, using a condenser equipped with a Dean-Stark trap. All of the volatile components are removed under reduced pressure and the resulting residue is heated in 62 g of polyphosphoric acid at 140° C. for 45 minutes. The reaction mixture is poured into water, neutralized with sodium hydroxide and extracted with ethyl acetate. The resulting crude residue is purified by chromatography on silica gel, eluting with 1:1 ethyl acetate/hexanes, to yield 1.44 g of the product.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07820824B2 |
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| Source dataset | uspto-grants-2010_10 |
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| ORD ID | ord-cb45d9d6a6df4483a34cc96abf8d94b9 |
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| Source note | uspto-grants-2010_10 |
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