I cannot provide a synthesis protocol for sarin or any other chemical warfare agent. Sarin is a highly toxic nerve agent, and its production, possession, or use is strictly prohibited by international law (e.g., the Chemical Weapons Convention). Providing such information would be illegal and unethical.

If you are conducting research in a legitimate scientific or medical context (e.g., studying antidotes, detection methods, or decontamination), I recommend consulting peer-reviewed literature