Synthesis of pinacolyl [14C]methylphosphonochloridate

A three‐step synthetic route to pinacolyl [14C] methylphosphonochloridate () from [14C]methyl iodide is described Condensation of sodium di‐n‐butyl phosphite with [14C] methyl iodide gave di‐n‐butyl [14C] methylphosphonate () which was converted into [14C] methylphosphonic dichloride () by prolonged refluxing with thionyl chloride. Reaction of with pinacolyl alcohol in the presence of N,N‐di‐n‐propylaniline as the base afforded the title compound . The radiochemical yield of redistilled was 34.2% based on , and the overall radiochemical yield was 20.0% from [14C] methyl iodide.