Sodium Hydroxide → N-Boc-cis-4-hydroxy-L-proline methyl ester

HRID 2185407Notes

Reaction equation

[OH-].[Na+].[CH3:3][O:4][C:5](=[O:21])[C@@H:6]1[CH2:10][C@H:9]([O:11]C=O)[CH2:8][N:7]1[C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15]>O1CCCC1>[CH3:3][O:4][C:5](=[O:21])[C@@H:6]1[CH2:10][C@H:9]([OH:11])[CH2:8][N:7]1[C:14]([O:16][C:17]([CH3:19])([CH3:18])[CH3:20])=[O:15]

Participants

Conditions

Temperature: 0 °C

Procedure

A solution of 1 N aqueous sodium hydroxide (6 mL) was added to a cold (0†° C.) stirred solution of N-tert-butoxycarbonyl-cis-4-formyloxy-L-proline methyl ester (I, 4.07 g) in tetrahydrofuran (6 mL). After stirring at 0° C. for 3 hr, a solution of 1 N aqueous sodium hydroxide (3 mL) was added and additionally stirred at 0° C. for 30 min. The mixture was evaporated in vacuo. The residue was diluted with ethyl acetate and washed with brine. The organic layer was dried over anhydrous sodium sulfate and evaporated in vacuo. The residue was purified by silica gel column chromatography (ethyl acetate:chloroform=1:5 to 1:1, v/v) to give the title compound (2.77 g) as a colorless oil: 1H NMR (400 MHz, CDCl3) δ 1.35-1.54 (m, 9H), 1.78 (br s, 1H), 2.00-2.15 (m, 1H), 2.27-2.39 (m, 1H), 3.50-3.59 (m, 1H), 3.61-3.71 (m, 1H), 3.63-3.77 (m, 1H), 3.78-3.80 (m, 3H), 4.29 (dd, J=1.5, 9.8 Hz, 1H), and 4.33-4.39 (m, 1H).

Workup

stirringadditionally stirred at 0° C. for 30 min
customThe mixture was evaporated in vacuo
additionThe residue was diluted with ethyl acetate
washwashed with brine
dry with materialThe organic layer was dried over anhydrous sodium sulfate
customevaporated in vacuo
customThe residue was purified by silica gel column chromatography (ethyl acetate

Sources & evidence

ORD record: ord-ae370ec92378431f9d595c0ba12d9eac
Source dataset: uspto-grants-2002_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06399629B1

Reaction notes

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