反応 #1999611

反応方程式

ammonium chloride

3-methylazetidine-1,2-dicarboxylic acid di-tert-butyl ester

1-bromo-3-methyl-2-butene

lithium hexamethyl disilazide

→

titled compound

3-methyl-2-(3-methyl-but-2-enyl)-azetidine-1,2-dicarboxylic acid di-tert-butyl ester

溶媒

tetrahydrofuran

water

反応条件

後処理

1. 1
   抽出the mixture was extracted with n-hexane/ethyl acetate (1/1, 500 ml)
2. 2
   洗浄The separated organic layer was sequentially washed with water (200 ml) and saturated aqueous sodium chloride solution (200 ml)
3. 3
   乾燥dried over anhydrous magnesium sulfate
4. 4
   濃縮concentrated under reduced pressure
5. 5
   その他The resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=15/1 to 8/1)

実験手順

To a solution of an optically-active compound of 3-methylazetidine-1,2-dicarboxylic acid di-tert-butyl ester (48.0 g) and 1-bromo-3-methyl-2-butene (25.4 ml) in tetrahydrofuran (380 ml) cooled to −69° C. was added lithium hexamethyl disilazide (1.0M tetrahydrofuran solution, 200 ml). The reaction mixture was warmed to −20° C. over 40 minutes, and stirred at the same temperature for additional 20 minutes. To the reaction mixture were sequentially added saturated aqueous ammonium chloride solution (200 ml) and water (300 ml), and the mixture was extracted with n-hexane/ethyl acetate (1/1, 500 ml). The separated organic layer was sequentially washed with water (200 ml) and saturated aqueous sodium chloride solution (200 ml), dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=15/1 to 8/1) to give the titled compound (44.5 g).

出典