Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Nicotinic acid, hydrazide | HCID 11112 | — |
| Reactant | Isobutyl chloroformate | HCID 62365 | — |
| Reactant | (2S,5R)-6-(Benzyloxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2-carboxylic acid | HCID 57389355 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 117988640 | HCID 117988640 | 78.8% |
Reaction Steps
A solution of the carboxylic acid (6b, 390 mg, 1.41 mmol) of Example 9 or 16 in dehydrated methylene chloride (14.1 mL) was cooled to 0° C. under an argon atmosphere, and isobutyl chloroformate (231.1 mg) was gradually added so that the temperature does not exceed 0° C. Then, triethylamine (185 mg) was gradually added so that the temperature does not exceed 0° C. followed by stirring for 30 minutes, thereby a mixed acid anhydride in the reaction system was prepared. To this reaction mixture was gradually added nicotinic acid hydrazide (580 mg). After the addition, the temperature was raised to room temperature, followed by stirring for 1 hour. This reaction mixture was washed with 0.5M hydrochloric acid and saturated brine, and the organic layer was dried over magnesium sulfate, and then distilled off under reduced pressure. The resulting residue was subjected to silica gel column chromatography (hexane/ethyl acetate=4/1-0/1, ethyl acetate/methanol=30/1) to afford 439.5 mg of the title compound as a colorless oil (yield 78.8%).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US09181250B2 |
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| Source dataset | uspto-grants-2015_11 |
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| ORD ID | ord-101dc95c62254c89bff19c66d61535d0 |
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| Source note | uspto-grants-2015_11 |
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