Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Acetic Anhydride | HCID 7918 | — |
| Reactant | Ethyl orthoformate | HCID 31214 | — |
| Reactant | Butanoic acid, 4,4-difluoro-3-oxo-, ethyl ester | HCID 67697 | — |
| Product | HCID 44185486 | HCID 44185486 | 74.8% |
Reaction Steps
To a freshly prepared solution of sodium ethoxide (prepared by addition of 1.11 g, 48.35 mmol Na metal in 8 mL EtOH) in EtOH was added a solution of ethyl difluoroacetate (5.0 g, 40.29 mmol) in EtOAc (9 mL) at rt and the reaction mixture was heated at 65° C. for 2 h. Then the reaction mixture was quenched with 1N HCl at rt and the pH was adjusted to 6-7. Then the reaction mixture was extracted with EtOAc and the organic layer was washed with water and brine, separated, dried, filtered and concentrated to afford 5.5 g of ethyl 4,4-difluoro-3-oxobutanoate which was taken to the next step without further purification. To a mixture of ethyl 4,4-difluoro-3-oxobutanoate (5.5 g, 33.11 mmol) and triethyl orthoformate (12 mL, 66.26 mmol) was added acetic anhydride (27.0 g, 265.0 mmol) and the reaction mixture was heated at 100° C. for 12 h. Then the reaction mixture was concentrated to afford 5.5 g of the title product which was taken to the next step without further purification.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09006257B2 |
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| Source dataset | uspto-grants-2015_04 |
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| ORD ID | ord-803ad3fa427a415e9c8d6a7078efdaf5 |
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| Source note | uspto-grants-2015_04 |
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