Recent progress in [¹¹ C]carbon dioxide ([¹¹ C]CO₂ ) and [¹¹ C]carbon monoxide ([¹¹ C]CO) chemistry

[¹¹ C]Carbon dioxide ([¹¹ C]CO₂ ) and [¹¹ C]carbon monoxide ([¹¹ C]CO) are 2 attractive precursors for labelling the carbonyl position (C═O) in a vast range of functionalised molecules (eg, ureas, amides, and carboxylic acids). The development of radiosynthetic methods to produce functionalised ¹¹ C-labelled compounds is required to enhance the radiotracers available for positron emission tomography, molecular, and medical imaging applications. Following a brief summary of secondary ¹¹ C-precursor production and uses, the review focuses on recent progress with direct ¹¹ C-carboxylation routes with [¹¹ C]CO₂ and ¹¹ C-carbonylation with [¹¹ C]CO. Novel approaches to generate [¹¹ C]CO using CO-releasing molecules (CO-RMs), such as silacarboxylic acids and disilanes, applied to radiochemistry are described and compared with standard [¹¹ C]CO production methods. These innovative [¹¹ C]CO synthesis strategies represent efficient and reliable [¹¹ C]CO production processes, enabling the widespread use of [¹¹ C]CO chemistry within the wider radiochemistry community.