反応 #49995

反応方程式

(3S,4S)-4-(1-hydroxymethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone

imidazole

t-butyldimethylchlorosilane

→

(3S,4S)-4-(1-t-butyldimethylsilyloxymethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone

溶媒

water

ethyl acetate

dimethylformamide

反応条件

後処理

1. 1
   抽出The aqueous layer was extracted with ethyl acetate (150 ml)
2. 2
   洗浄The combined extracts were washed successively with 5% hydrochloric acid solution (80 ml×2) and brine (80 ml)
3. 3
   乾燥dried over anhydrous sodium sulfate
4. 4
   ろ過After filtration
5. 5
   濃縮the filtrate was concentrated in vacuo
6. 6
   その他the concentrate was crystallized from isopropanol

実験手順

A solution of (3S,4S)-4-(1-hydroxymethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone (20 g) and imidazole (5.6 g) in dry dimethylformamide (45 ml) was treated with t-butyldimethylchlorosilane (6.77 g) at room temperature for 2 hours. The reaction mixture was diluted with cold water (200 ml) and ethyl acetate (150 ml). The aqueous layer was extracted with ethyl acetate (150 ml). The combined extracts were washed successively with 5% hydrochloric acid solution (80 ml×2) and brine (80 ml), and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated in vacuo, and the concentrate was crystallized from isopropanol to give crystals of (3S,4S)-4-(1-t-butyldimethylsilyloxymethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone. m.p., 90°-92° C.

出典