in acetonitrile 16 h;

1: ethyl (2R,3R,4S)-(+)-2-(4-methoxyphenyl)-4-(1,3-benzodioxol-5-yl)pyrrolidine-3-carboxylate, (S)-(+)-mandelate With sodium hydrogencarbonate in water; ethyl acetate T=25°C; 2: BrCH2CONBu2 With N-ethyl-N,N-diisopropylamine in acetonitrile T=10°C; 12 h; 3: With hydrogenchloride; sodium hydroxide more than 3 stages;