反应详情

To (S)-1-(((9H-fluoren-9-yl)methoxy)carbonyl)-2-methylpyrrolidine-2-carboxylic acid (intermediate LS30; 1.5 g; 4.3 mmol) in 50 mL DMF was added sequentially 2-amino-1-(4-bromophenyl)ethanone hydrochloride (1.2 g; 4.7 mmol), HOAT (290 mg; 2.1 mmol), Hunig's base (0.7 mL; 4.3 mmol) and EDCI (1.2 g; 6.4 mmol). After 1 h, the reaction mixture was poured into 150 mL water and allowed to stir for 15 min before filtering the resultant precipitate which was dissolved in dichloromethane and dried over magnesium sulfate. The dichloromethane mixture was filtered and applied to a Biotage 40 samplet. Chromatography on a 40M column (25 to 60% ethyl acetate/hexane over 1200 mL) provided (S)-(9H-fluoren-9-yl)methyl 2-(2-(4-bromophenyl)-2-oxoethylcarbamoyl)-2-methylpyrrolidine-1-carboxylate (intermediate LS31; 2.4 g; quant) as a yellow foam. LC (Cond'n 11): RT=3.75 min; MS: Anal. Calcd. for [M+H]+ C29H27BrN2O4: 547.1; found 547.0.

1. filtrationbefore filtering the resultant precipitate which
2. dissolutionwas dissolved in dichloromethane
3. dry with materialdried over magnesium sulfate
4. filtrationThe dichloromethane mixture was filtered