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ChemicalBook CAS DataBase List BOC-CYS-OH
20887-95-0

BOC-CYS-OH synthesis

11synthesis methods
-

Yield:20887-95-0 97%

Reaction Conditions:

with sodium hydroxide in 1,4-dioxane;water at 20;Cooling with ice;

Steps:

1.1 Step 1: Preparation of N-Boc-L-cysteine (1)
Add L-cysteine (6.0 g, 50 mmol), NaOH (1.2 g, 50 mmol),Dioxane (30 mL) and water (50 mL), (Boc) 2O (17.0 g, 70 mmol) were added under an ice bath, and stirring was continued at room temperature overnight. Concentrated under reduced pressure to remove dioxane,The aqueous layer was extracted with ethyl acetate to remove unreacted Boc anhydride.The aqueous layer was adjusted to pH 1-2 with 1 mol / L hydrochloric acid, and extracted twice with ethyl acetate.The organic phases were combined and washed with saturated brine, dried over anhydrous sodium sulfate,Concentrated under reduced pressure to obtain 2.15 g (1) as a colorless syrup, with a yield of 97%.Directly used for the next reaction

References:

Fudan University;Chu Yong;Gao Yang;Ye Deyong CN110407770, 2019, A Location in patent:Paragraph 0036-0040

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