Abstract

Development of a High Purity Continuous Flow Synthesis of Diazepam

David Thompson, Professor, Purdue University

We report an optimized two-step continuous flow synthesis of diazepam, an agent on the World Health Organization’s (WHO) list of essential medicines. Different conditions were rapidly screened in microfluidic chip reactors where the residence time, temperature, solvent, and ammonia sources were varied to identify the best telescoped reaction conditions. The optimal flow process uses two telescoped reactors operating at 0°C for the first step and 60°C for the second step to produce 98% pure diazepam with a total residence time of 15 minutes.