Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Dimethylformamide | HCID 6228 | — |
| Reactant | Sodium Hydroxide | HCID 14798 | — |
| Reactant | Phosphorus oxychloride | HCID 24813 | — |
| Reactant | HCID 178429390 | HCID 178429390 | — |
| Solvent | 1,2-Dichloroethane | HCID 11 | — |
| Solvent | Water | HCID 962 | — |
| Solvent | 1,1-Dichloroethane | HCID 6365 | — |
| Product | Methylhydrazine | HCID 6061 | — |
| Product | 5-Chloro-1,3-dimethylpyrazole-4-carboxaldehyde | HCID 2777397 | — |
Reaction Steps
To DMF (33.29 mL, 0.456 mol) was carefully added POCl3 (134.16 g, 81.5 mL 0.874 mol,) at 0° C. The reaction mixture was diluted with 1,2-dichloroethane (100 mL), then treated with a solution of crude 1,3-dimethyl-1H-pyrazol-5-ol (50 g, from Step 1) in dichloroethane (100 mL) under continued stirring at 0° C. The mixture was refluxed for 3 h, then left to stir overnight at room temperature. In order to decompose the formylating reagent, to the reaction mixture was added a solution of sodium hydroxide (91.2 g, 2.28 mol) in water (200 mL) dropwise at 0° C. The reaction mixture was diluted with water and extracted with dichloromethane (3×250 mL). The organic extracts were washed with water to neutral pH, washed with water, then dried with sodium sulfate. The solvent was removed under vacuum to afford the title product (31.1 g, 51% overall from methylhydrazine) as a yellow crystalline substance.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08268835B2 |
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| Source dataset | uspto-grants-2012_09 |
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| ORD ID | ord-5d192f7b719b41ec9940468b9949c2b8 |
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| Source note | uspto-grants-2012_09 |
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