Method for preparing (S)-3-piperidinecarboxylic acid

The invention discloses a method for preparing (S)-3-piperidinecarboxylic acid. The method includes steps of carrying out reaction on 3-piperidinecarboxamide or salt of the 3-piperidinecarboxamide in concentrated hydrochloric acid to obtain (S)-3-piperidinecarboxylic acid salt; converting the (S)-3-piperidinecarboxylic acid salt to obtain the (S)-3-piperidinecarboxylic acid. The method has the advantages that the reaction is carried out on the 3-piperidinecarboxamide or the salt of the 3-piperidinecarboxamide in the concentrated hydrochloric acid, accordingly, chiral resolution effects can be realized while hydrolysis is carried out, and resolution on the 3-piperidinecarboxamide or 3-piperidinecarboxylic acid by the aid of chiral resolving agents can be omitted; preparation processes are simple in post-treatment operation, N protection and de-protection processes are omitted, accordingly, the method is high in atomic economy and low in cost, and a simple, feasible and low-cost production method can be provide