Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Carbon Dioxide | HCID 280 | — |
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Ethyl chloroformate | HCID 10928 | — |
| Reactant | Sodium Bicarbonate | HCID 516892 | — |
| Reactant | NSC55572 | HCID 5356375 | — |
| Solvent | Water | HCID 962 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Product | HCID 12079073 | HCID 12079073 | 89.8% |
Reaction Steps
In a round bottom flask with a nitrogen atmosphere and containing a mechanical stirrer, a thermometer, an addition funnel and a condenser, was combined 700 grams (4.0 moles) of (Z)-4-(tert-butylamino)-4-oxo-2-butenoic acid and 7,757 grams dichloromethane. The mixture was cooled to −5° C. and 439 grams (4.0 moles) ethyl chloroformate (commercially available from Aldrich Chemical, Milwaukee, Wis.) was added. The mixture was cooled to −10° C. and 409 grams (4.0 moles) triethylamine (commercially available from Aldrich Chemical, Milwaukee, Wis.) was added slowly at a rate such that the temperature remained below −7° C. Stirring was continued at −5° C. for 2.5 hours during which time the evolution of carbon dioxide was observed. The mixture was warmed to 11° C. and a premix of 272 grams of sodium bicarbonate dissolved in 3,640 grams of distilled water was added. The mixture was stirred for 10 minutes, allowed to phase separate, and the aqueous phase was removed. The organic phase was extracted three times, each time with 3 liters of distilled water. The organic phase was dried with 275 grams of sodium sulfate, filtered and the solvent was removed in vacuo at 30° C. The residue was purified by distillation (50° C., 0.05 millimeters of Hg) to give 550 grams of 5-(tert-butylimino)-2,5-dihydro-2-furanone. This material is hereinafter referred to as TBIMI (tert-butylisomaleimide). 13C NMR indicated the product to be >99% pure.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US06440573B1 |
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| Source dataset | uspto-grants-2002_08 |
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| ORD ID | ord-70f298fd51e647cfa471c8fec1b79cbe |
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| Source note | uspto-grants-2002_08 |
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