Unlocking full and fast conversion in photocatalytic carbon dioxide reduction for applications in radio-carbonylation

Harvesting sunlight to drive carbon dioxide (CO2) valorisation represents an ideal concept to support a sustainable and carbon-neutral economy. While the photochemical reduction of CO2 to carbon monoxide (CO) has emerged as a hot research topic, the full CO2-to-CO conversion remains an often-overlooked criterion that prevents a productive and direct valorisation of CO into high-value-added chemicals. Herein, we report a photocatalytic process that unlocks full and fast CO2-to-CO conversion (<10 min) and its straightforward valorisation into human health related field of radiochemistry with carbon isotopes. Guided by reaction-model-based kinetic simulations to rationalize reaction optimisations, this manifold opens new opportunities for the direct access to 11C- and 14C-labeled pharmaceuticals from their primary isotopic sources [11C]CO2 and [14C]CO2

Carbon isotope labeling of carbamates by late-stage [11C], [13C] and [14C]carbon dioxide incorporation

A general procedure for the late-stage [11C], [13C] and [14C]carbon isotope labeling of cyclic carbamates is reported. This protocol allows the incorporation of carbon dioxide, the primary source of carbon-14 and carbon-11 radioisotopes, in a direct, cost-effective and sustainable manner. A disconnection/reconnection strategy, involving ring opening/isotopic closure, was also implemented

General Procedure for Carbon Isotope Labeling of Linear Urea Derivatives with Carbon Dioxide

Carbon isotope labeling is a traceless technology, which allows tracking the fate of organic compounds either in the environment or in living organisms. This article reports on a general approach to label urea derivatives with all carbon isotopes, including 14C and 11C, based on a Staudinger aza-Wittig sequence. It provides access to all aliphatic/aromatic urea combinations

A Photochemical Strategy for Carbon Isotope Exchange with CO2

A photocatalytic approach for carbon isotope exchange is reported. Utilizing [13C]CO2 and [14C]CO2 as primary C1 sources, this protocol allows the insertion of the desired carbon isotope into phenyl acetic acids without the need for structural modifications or prefunctionalization in one single step. The exceptionally mild conditions required for this traceless trans- formation are in stark contrast with those for previous methods requiring the use of harsh thermal conditions