ChemicalBook CAS DataBase List BOC-L-Asparagine

BOC-L-Asparagine synthesis

10synthesis methods

Product Name:BOC-L-Asparagine
CAS Number:7536-55-2
Molecular formula:C9H16N2O5
Molecular Weight:232.23

70-47-3

24424-99-5

7536-55-2

L-asparagine (15 g, 0.113 mol, 1.0 eq.) and sodium carbonate (12 g, 0.113 mol, 1.0 eq.) were dissolved in a solvent mixture of water (225 mL) and 1,4-dioxane (225 mL) at room temperature. To this solution was slowly added di-tert-butyl dicarbonate (30 g, 0.137 mol, 1.2 eq.) and the reaction mixture was stirred overnight at room temperature. Upon completion of the reaction, 1,4-dioxane was removed by distillation under reduced pressure. Subsequently, the pH of the solution was adjusted to 2 with 37% hydrochloric acid, at which point a white solid precipitated. The solid product was collected by filtration, washed with water and dried under appropriate conditions. Finally, 24 g of BOC-L-asparagine was obtained in 91% yield. The product characterization data were as follows: melting point 175°C-180°C (literature value 175°C); 1H NMR (DMSO-D6) δ 12.5 (1H, br); 7.31 (1H, br); 6.91 (1H, br); 6.87 (1H, d, J=8.4 Hz); 4.23 (1H, q, J=7.7 Hz); 2.56- 2.36 (2H, m); 1.38 (9H, s).

70-47-3 Synthesis

70-47-3
562 suppliers
$6.00/10g

24424-99-5 Synthesis

24424-99-5
867 suppliers
$13.50/25G

7536-55-2
345 suppliers
$7.00/10g

Yield:7536-55-2 91%

Reaction Conditions:

with sodium carbonate in 1,4-dioxane;water at 20;

Steps:

G.5.1
L-asparagine (15 g, 0.113 mol, LEQ.) and sodium carbonate (12 g, 0.113 mol) were dissolved in water (225 ML) and 1, 4-dioxane (225 ml) at r. T.. To this solution, di-tert-butyl-dicarbonate (30 g, 0.137 mol, 1.2 eq. ) was added and the mixture was stirred overnight. The solvent was evaporated under reduced pressure till 1,4-dioxane was distilled and the pH adjusted to 2 with HCI 37% to give a white solid that was filtered, washed with water and dried. Yield 91%. 24g. Analytical data: m. p. 175°C-180°C (lit. 175°C). 'H NMR (DMSO-D6) 12.5 (1H, br); 7.31 (1H, BR) ; 6.91 (1H, br); 6.87 (1H, d, J=8. 4 Hz); 4.23 (1H, q, J=7. 7 HZ) ; 2.56-2. 36 (2H, M) ; 1.38 (9H, s).

References:

CEPHALON, INC.;SEDE SECONDARIA DELLA CELL THERAPEUTICS, INC. WO2005/21558, 2005, A2 Location in patent:Page/Page column 214

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1070-19-5 Synthesis