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ChemicalBook CAS DataBase List N-Cbz-Hydroxy-L-proline
13504-85-3

N-Cbz-Hydroxy-L-proline synthesis

7synthesis methods
-

Yield:13504-85-3 190 g

Reaction Conditions:

with sodium hydrogencarbonate;sodium carbonate in acetone at 22; for 15 h;Cooling with ice;

Steps:

9.1 Preparation of (254R)-1 -(benzyloxycarbonyl)-4-hydroxypyrrolidine-2-carboxylic acid.

To a 3 L flask were added (25,4R)-4-hydroxypyrrolidine-2-carboxylic acid (87.0 g,663.46 mmol, 1.0 eq.), water (1500 ml), Na2CO3 (141.0 g, 1330 mmol, 2.0 eq.) andNaHCO3 (55.7 g, 663 mmol, 1.0 eq.). Acetone (250 ml) was added to the solution which was then cooled in an ice-water bath. To the mixture was slowly added Cbz-Cl (141.0 g, 829 mmol, 1.25 eq.). After addition, the reaction mixture was warmed gradually to 22 °C and was stirred for 15 h. The reaction mixture was washed with MTBE (600 ml x 2). To the aqueous phase was slowly added aqueous 1 N HCI until pH-2 was achieved. The resulting mixture was extracted with EtOAc (1 L x 3) and the combined organic layer was dried over MgSO4, filtered and concentrated underreduced pressure to provide 190 g of the title compound as an oil, which was taken to the next step without further purification. LCMS: MS = 287.8 (M+H).

References:

WO2018/20358,2018,A1 Location in patent:Page/Page column 84; 85

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