Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Allyl bromide | HCID 7841 | — |
| Reactant | 1-((Tert-butoxy)carbonyl)-4,4-difluoropyrrolidine-2-carboxylic acid | HCID 23512514 | — |
| Catalyst | Trioctylmethylammonium chloride | HCID 21218 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Solvent | Sodium Bicarbonate | HCID 516892 | — |
| Product | HCID 59853567 | HCID 59853567 | 74.5% |
Reaction Steps
4,4-Difluoro-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester (Example 14b, 6.77 g, 26.96 mmol) was dissolved in a 5% aqueous sodium bicarbonate solution (50 mL). Allyl bromide (3.26 g, 26.96 mmol) and trioctylmethylammonium chloride (“Aliquat® 336”, 10.90 g, 26.97 mmol) were dissolved in dichloromethane (50 mL) and were added to the aqueous solution. The biphasic reaction mixture was stirred vigorously for 48 h at 25° C. The layers were separated and the aqueous layer was extracted with dichloromethane (3×70 mL). The combined organic layers were dried over sodium sulfate and filtered. The solvent was removed in vacuo to afford the crude desired product, which was purified by flash column chromatography (Merck silica gel 60, 40-63 μm, 20% ethyl acetate in hexanes) to afford the desired product, 4,4-difluoro-pyrrolidine-1,2-dicarboxylic acid 2-allyl ester 1-tert-butyl ester (5.85 g, 20.09 mmol, 74.5% yield) as a clear, slightly yellowish oil. 1H NMR (400 MHz, CDCl3) δ: 1.44 (9H, s), 2.43-2.54 (1H, m), 2.64-2.80 (1H, m), 3.78-3.94 (2H, m), 4.46-4.73 (3H, m), 5.24-5.37 (2H, m), 5.87-5.96 (1H, m).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US07582754B2 |
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| Source dataset | uspto-grants-2009_09 |
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| ORD ID | ord-62a3876f2f5b4ec2999ef7fda50b9f8c |
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| Source note | uspto-grants-2009_09 |
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