Process for preparing ethyl (S)-2-ethoxy-4-[N-[1-(2-piperidinophenyl)-3-methyl-1-butyl]aminocarbonyl methyl]benzoate and use thereof for the preparation of Repaglinide

Described herein is an improved, commercially viable and industrially advantageous process for the preparation of Repaglinide intermediate, ethyl (S)-2-ethoxy-4-[N-(1-(2-piperidino-phenyl)-3-methyl-1-butyl)-aminocarbonylmethyl]-benzoate. The process provides the Repaglinide intermediate in higher yield and purity compared to the previously disclosed processes, thereby providing for production of Repaglinide and its pharmaceutically acceptable salts in high purity and in high yield.