Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Formaldehyde | HCID 712 | — |
| Reactant | Sodium cyanoborohydride | HCID 5003444 | — |
| Reactant | (4R)-4-Hydroxy-L-proline methyl ester | HCID 7015125 | — |
| Solvent | Methanol | HCID 887 | — |
| Product | HCID 15594656 | HCID 15594656 | — |
Reaction Steps
Methyl (2S,4R)-4-hydroxypyrrolidine-2-carboxylate 3a (5.53 g, 38 mmol) was dissolved in 80 mL of methanol in an ice-water bath, followed by addition of 40% formaldehyde solution (31 mL, 380 mmol) and sodium cyanoborohydride (12 g, 190 mmol) in batches. The reaction mixture was stirred for 0.5 hours, then warmed up to room temperature and stirred for 3 hours. The mixture was quenched with 40 mL of water, concentrated under reduced pressure and extracted with dichloromethane (80 mL×3). The combined organic extracts were washed with saturated brine (30 mL×2), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain the title compound methyl (2S,4R)-4-hydroxy-1-methyl-pyrrolidine-2-carboxylate 3b crude product as a colourless oil, which was directly used in the next step.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08901140B2 |
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| Source dataset | uspto-grants-2014_12 |
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| ORD ID | ord-840827f382c346e3b2ea0fcad5edb494 |
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| Source note | uspto-grants-2014_12 |
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