反応 #45391

反応方程式

(L)-valine methyl ester hydrochloride

magnesium sulfate

6-bromopyridine-2-carboxaldehyde

triethylamine

→

(S)-2-{[1-(6-Bromo-pyridin-2-yl)-meth-(E)-ylidene]-amino}-3-methyl-butyric acid methyl ester

反応条件

後処理

1. 1
   workup.ADDITIONeach added sequentially in one portion to
2. 2
   ろ過The mixture was then filtered
3. 3
   洗浄the filter cake washed with diethyl ether (100 mL)
4. 4
   その他before evaporating the filtrate in vacuo
5. 5
   その他The residue was purified by column chromatography
6. 6
   その他to yield A469.1 (7.1 g, 88%)
7. 7
   その他4.6×33 mm (2 min grad)

実験手順

Anhydrous magnesium sulfate (5.4 g), 6-bromopyridine-2-carboxaldehyde (5.0 g, 26.9 mmol) and triethylamine (3.75 mL, 26.9 mmol) were each added sequentially in one portion to a cooled (0° C.) solution of (L)-valine methyl ester hydrochloride (4.51 g, 26.9 mmol) and the reaction mixture was allowed to warm slowly to room temperature overnight under a nitrogen atmosphere. The mixture was then filtered and the filter cake washed with diethyl ether (100 mL) before evaporating the filtrate in vacuo. The residue was purified by column chromatography using 5:1 hexane/ethyl acetate as eluent to yield A469.1 (7.1 g, 88%). HPLC YMC S-5 4.6×33 mm (2 min grad): retention time 0.86 min, M+H+=202.08

出典