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ChemicalBook CAS DataBase List (2R,4S)-N-ALPHA-T-BUTOXYCARBONYL-4-HYDROXYPYRROLIDINE-2-CARBOXYLIC ACID
147266-92-0

(2R,4S)-N-ALPHA-T-BUTOXYCARBONYL-4-HYDROXYPYRROLIDINE-2-CARBOXYLIC ACID synthesis

6synthesis methods
Di-tert-butyl dicarbonate

24424-99-5

L-Hydroxyproline

51-35-4

(2R,4S)-N-ALPHA-T-BUTOXYCARBONYL-4-HYDROXYPYRROLIDINE-2-CARBOXYLIC ACID

147266-92-0

General procedure for the synthesis of N-BOC-trans-4-hydroxy-D-proline from di-tert-butyl dicarbonate and L-hydroxyproline: Step A: Preparation of (4β)-1-Boc-4-hydroxy-L-proline 1. dissolve L-hydroxyproline (5.08 g, 38.77 mmol) in a solvent mixture of 1N NaOH solution (40 mL) and 1,4-dioxane (40 mL). 2. Di-tert-butyl dicarbonate (9.3 g, 42.6 mmol) was added drop-wise to the above solution at 0 °C. 3. The reaction mixture was stirred at room temperature for 8 hours. 4. 4. After completion of the reaction, the mixture was concentrated under vacuum to remove the solvent. 5. The concentrated mixture was acidified with 1N HCl and then extracted with EtOAc. 6. The organic extract was washed with brine, dried over MgSO4 and filtered. 7. Finally, the filtrate was concentrated under vacuum to give N-BOC-trans-4-hydroxy-D-proline (8.84 g, 99% yield). MS [M + H] = 232 (M + 1).

-

Yield:147266-92-0 90%

Reaction Conditions:

with sodium hydroxide in 1,4-dioxane at 0 - 20;

Steps:

1.A
Preparation 1: Methyl (25,45)-l-Boc-4-aminopyrrolidin-2-carboxyIate [285] Step A: (4/?)-l-Boc-4-hydroxy-L-proline [286] (4/?)-hydroxy-L-proline (5.08 g, 38.77 mmol) was dissolved in IN NaOH (40 ml) and 1,4-dioxane (40 ml), and to the resulting solution, di-t-butyl dicarbonate (9.3g, 42.6 mmol) was added dropwise at 00C. The reaction mixture was stirred at room tem? perature for 8 hours, concentrated in vacuo, acidified with IN HCl, and extracted with EtOAc. The organic extracts were washed with brine, dried over MgSO4, filtered, and concentrated in vacuo to give the title compound (8.84g, 99 %).[287] MS[M+H] = 232 (M+l) [288] [289]

References:

LG LIFE SCIENCES LTD. WO2010/56022, 2010, A2 Location in patent:Page/Page column 21

FullText

(2R,4S)-N-ALPHA-T-BUTOXYCARBONYL-4-HYDROXYPYRROLIDINE-2-CARBOXYLIC ACID Related Search:

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