An improved synthesis of substituted [11C]toluenes via Suzuki coupling with [11C]methyl iodide

Toluene derivatives are often found in drug‐like molecules, and are therefore desirable as radiolabelled moieties. The desire for an alternate to the Stille coupling led us to investigate the feasibility of the Suzuki coupling. We have found the Suzuki coupling route to be a robust alternative to the Stille coupling for the synthesis of functionalized [¹¹C]toluene derivatives from [¹¹C]methyl iodide. The avoidance of potentially toxic tin‐containing by‐products is an added advantage. The products synthesized via Suzuki coupling with [¹¹C]methyl iodide were isolated in generally high yields (56–92%), with high radiochemical purity (>95%) and specific radioactivity (>4000 Ci/mmol) in less than 20 min following production of [¹¹C]methyl iodide. Copyright © 2005 John Wiley & Sons, Ltd.