1: With diisobutylaluminium hydride in dichloromethane; toluene T=-78°C; 1 h; Inert atmosphere; 2: With methanol; Potassium sodium tartrate in dichloromethane; toluene T=20°C;

ammonium hydroxide in methanol; water T=20°C; Inert atmosphere;

1.1: methyl-magnesium chloride / tetrahydrofuran / 0.5 h / 10 °C / Inert atmosphere 1.2: 2.75 h / 10 °C / Reflux 2.1: aluminum isopropoxide; isopropyl alcohol / 3 h / Reflux 3.1: sodium hydroxide / acetone / 1.5 h / 20 °C View Scheme

water; lithium hydroxide hydrate in tetrahydrofuran; methanol T=0°C; 6 h;

diisobutylaluminium hydride in hexane; dichloromethane T=20°C; Reduction; 3 h;

hydrogenchloride in methanol

1: N-tert-butoxycarbonyl-L-phenylalanine With 4-methyl-morpholine; benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride in N,N-dimethyl-formamide T=0°C; Inert atmosphere; 2: methyl (2R)-2-(t-butoxycarbonylamino)-3-phenylpropionate With 4-methyl-morpholine in N,N-dimethyl-formamide T=20°C; Inert atmosphere;

1: With methyl-magnesium chloride in tetrahydrofuran T=10°C; 0.5 h; Inert atmosphere; 2: With methyl-magnesium chloride; diisopropylamine in tetrahydrofuran T=10°C; 2.75 h; Reflux;

1: 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine / dichloromethane 2: methanol; water; lithium hydroxide hydrate / tetrahydrofuran View Scheme