反应详情

温度

3.5 °C

A mixture of (S)-2-[4-(3-fluorobenzyloxy)benzylideneamino]propanamide (III a) (150 g), prepared as described in Example 16a), and methanol (900 mL) is cooled under stirring to 2-5° C. Sodium borohydride (19.0 g) is added in small portions in 2 hours to the previously prepared cold mixture keeping the temperature below 5° C. The mixture is then stirred for additional 20 min at 5° C. The reaction mixture is concentrated under vacuum and worked up as described in Example 2 to give 135 g (89.2% yield) of (5)-2-[4-(3-fluorobenzyloxy)benzylamino]propanamide (Ia) with a HPLC purity of 98.8 (area % determined according to the method of Example 25A and a C,O-dialkylated (S)-2-[3-(3-fluorobenzyl)-4-(3-fluorobenzyloxy)-benzylamino]propanamide content of 0.005% by weight determined by HPLC, according to the method of Example 25B.

1. customprepared
2. temperatureis cooled
3. customthe temperature below 5° C
4. stirringThe mixture is then stirred for additional 20 min at 5° C
5. concentrationThe reaction mixture is concentrated under vacuum