1: 82 percent / phosphate buffer, aq. NaOH / pig liver esterase / acetone / 7 h / 25 °C / pH 8 2: 83 percent / 4-dimethylaminopyridine, dicyclohexylcarbodiimide / CH2Cl2 / 1.) 0 deg C, 5 min, 2.) r.t., 3 h 3: 81 percent / aq. NaOH / methanol / 2.5 h / Ambient temperature 4: 67 percent / 2-isobutyloxy-1-isobutyloxycarbonyl-1,2-dihydroquinoline / tetrahydrofuran / 1.) r.t., 2.) reflux 5: 76 percent / CF3COOH / CH2Cl2 / 1.5 h / Ambient temperature 6: 30 percent / H2 / 10percent Pd-C / methanol / 20 °C View Scheme

triethylamine

potassium carbonate in diethyl ether T=20°C; 3 h;

1.1: NH4Cl; 3 Angstroem molecular sieves / methanol / 12 h 1.2: NaBH3CN; HCl / methanol / pH 3 2.1: 30.29 g / aq. K2CO3 / diethyl ether / 3 h / 20 °C View Scheme

1: 82 percent / phosphate buffer, aq. NaOH / pig liver esterase / acetone / 7 h / 25 °C / pH 8 2: 83 percent / 4-dimethylaminopyridine, dicyclohexylcarbodiimide / CH2Cl2 / 1.) 0 deg C, 5 min, 2.) r.t., 3 h 3: 81 percent / aq. NaOH / methanol / 2.5 h / Ambient temperature View Scheme