反应详情

To a stirred solution of 3.09 g (13.5 mmol) of DL-3,4-dichloromandelic acid, 3.0 g (13.5 mmol) of trans-4-(2-amino-cyclohexyl)-2-methoxy-phenol and 1.89 (13.5 mmol) of N,N-diisopropylethylamine in 30 ml DMF is added 6.0 g (13.5 mmol) of benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate in one portion. The reaction mixture is then stirred at ambient temperature for about 2 hours and thereafter poured into 150 ml of aqueous saturated sodium chloride solution. The two-phase mixture is extracted with two 150 ml portions of ethyl acetate. The organic extract is concentrated under reduced pressure to a residue, which is subjected to column chromatography on silica gel, with 1:1 ethyl acetate/isohexane as the eluant yielding 2-(3,4-dichlorophenyl)-2-hydroxy-N-[trans-2-(4-hydroxy-3-methoxy-phenyl)-cyclohexyl]-acetamide.

1. extractionThe two-phase mixture is extracted with two 150 ml portions of ethyl acetate
2. extractionThe organic extract
3. concentrationis concentrated under reduced pressure to a residue, which