反応 #63991

反応方程式

dicyclohexylcarbodiimide

N-t-butoxycarbonyl-L-alanine

D-alanine benzyl ester p-toluenesulfonic acid salt

triethylamine

→

N-t-butoxycarbonyl-L-alanyl-D-alanine benzyl ester

溶媒

methylene chloride

methylene chloride

反応条件

後処理

1. 1
   ろ過were filtered
2. 2
   濃縮the filtrate concentrated to an oil
3. 3
   workup.DISSOLUTIONThe residue was dissolved in 400 ml
4. 4
   洗浄of ethyl acetate which was washed with a 1% hydrochloric acid solution
5. 5
   その他The organic phase was separated
6. 6
   乾燥dried over magnesium sulfate
7. 7
   濃縮concentrated to an oil
8. 8
   その他The residue was triturated with diethyl ether
9. 9
   ろ過the resulting solids filtered under nitrogen
10. 10
    その他of the desired product crystallized from the filtrate

実験手順

To a solution of 23.0 g. (0.121 m) of N-t-butoxycarbonyl-L-alanine, 42.6 g. (0.121 m) of D-alanine benzyl ester p-toluenesulfonic acid salt and 17 ml. (0.121 m) of triethylamine in 400 ml. of cold (0° C.) methylene chloride was added dropwise 25.0 g. (0.121 m) of dicyclohexylcarbodiimide in 100 ml. of methylene chloride. After stirring overnight at room temperature the solids were filtered and the filtrate concentrated to an oil. The residue was dissolved in 400 ml. of ethyl acetate which was washed with a 1% hydrochloric acid solution, a 10% potassium carbonate solution, water and a brine solution. The organic phase was separated, dried over magnesium sulfate and concentrated to an oil. The residue was triturated with diethyl ether and the resulting solids filtered under nitrogen, 16.0 g. An additional 12.7 g. of the desired product crystallized from the filtrate.

出典