Method for preparing N-[1-(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine by continuous flow method

The invention provides a method for preparing N-[1-(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine through a continuous flow method, and belongs to the technical field of pharmaceutical engineering. The method for preparing the N-[1-(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine by the continuous flow method provided by the invention comprises the following steps: mixing the N-[1-(S)-ethoxycarbonyl-3-oxo-phenylpropyl]-L-alanine, an organic solvent and a strong acid reagent to obtain a reaction solution; and introducing the reaction solution into a continuous flow reactor filled with a noble metal catalyst, and carrying out a hydrogenation reaction in the presence of hydrogen to obtain the N-[1-(S)-ethoxycarbonyl-3-phenylpropyl]-L-alanine. Compared with a traditional kettle type reaction method, the continuous flow method is high in reaction activity, short in reaction time, capable of reducing generation of by-products and impurities, high in product yield and purity, and capable of reducing nearly 90% of reactor