Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Hydrazine | HCID 9321 | — |
| Reactant | 1,1,3,3-Tetraethoxy-2-methylpropane | HCID 82761 | — |
| Product | 4-Methylpyrazole | HCID 3406 | — |
| Product | Hydrazine hydrate (1:1) | HCID 24654 | — |
Reaction Steps
In the first step of the present synthesis of 4-MP, propionaldehyde is reacted with triethyl orthoformate in the presence of ethanol and ammonium nitrate to produce 1,1-diethoxypropane. In the second step, the 1,1-diethoxypropane produced in the first step is reacted neat (without a solvent) with a catalyst, which comprises an acid and an amine, to produce 1-ethoxy-1-propene (ethyl-1-propenyl ether). In the third step, this material is purified by washing and drying, without distillation. In the fourth step, the 1-ethoxy-1-propene from the third step is reacted with triethyl orthoformate in the presence of boron trifluoride-diethyl etherate to produce 1,1,3,3-tetraethoxy-2-methyl propane (“TEMP”). In the fifth step, the TEMP from the third step is reacted with hydrazine or a hydrazonium salt or hydrazine hydrate at elevated temperatures to produce 4-methylpyrazole.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07553863B2 |
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| Source dataset | uspto-grants-2009_06 |
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| ORD ID | ord-de85b070ecdd4482b2defd00114b5614 |
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| Source note | uspto-grants-2009_06 |
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