Photocatalyzed radiosynthesis of 11C-phenylacetic acids

Abstract

Fast and straightforward incorporation of radionuclides into pharmaceutically relevant molecules is one of the main barriers to preclinical and clinical tracer research. Late-stage direct incorporation of cyclotron-produced [¹¹C]CO₂ to afford carbon-11-labeled radiopharmaceuticals has the potential to provide ready-to-inject positron emission tomography agents in less than an hour. The present work describes photocatalyzed carboxylation of alkylbenzene derivatives to afford ¹¹C-phenylacetic acids. Reaction conditions and scope are investigated followed by application of this methodology to the preparative radiosynthesis of [¹¹C]fenoprofen, a nonsteroidal anti-inflammatory drug.