Organometallic Chemistry for Enabling Carbon Dioxide Utilization

Abstract

<p>In photosynthesis, carbon dioxide is used as the carbon source; indeed, most carbon atoms in the structure of a massive tree—the trunk, the branches, the leaves—originate from CO2. This insight has profound implications for chemical synthesis: complex molecular structures are built from something as simple and inert as CO₂. Scientists have long been fascinated by this concept, and chemists have tried to reproduce it by generating artificial systems for the transformation of CO₂ into more valuable products. <p>Over the past two decades, chemical conversion of CO₂ has developed into a major research field. Several comprehensive reviews have summarized advances on coupling CO₂ with nucleophiles to form carboxylic acids, carbonates, or carbamates or on reducing CO₂ to C1 species such as formate and methanol. The reviews of this field also emphasize an important point: chemical utilization of CO2 is not a strategy to mitigate climate change. CO₂ is, however, a renewable carbon feedstock that can replace nonrenewable fossil-fuel-based starting materials. Therefore, methods for the efficient conversion of CO₂ should be viewed as an integral part in the development of sustainable chemical processes. <p>The 22 articles in this Special Issue highlight the many ways in which organometallic chemistry can help solve challenges related to CO₂ utilization: organometallic complexes can be used in thermal, electrochemical, or photochemical conversion of CO₂ to various products such as formate, carbon monoxide, carboxylic acids, acrylates, and polycarbonates. Remarkably, the work presented here involves the activation of CO₂ with 15 different metals, including the first-row transition metals titanium, manganese, iron, cobalt, nickel, and copper, the second-row elements ruthenium and rhodium, the third-row species rhenium, platinum, and iridium, the actinide uranium, and the main-group metals cesium, magnesium, and aluminum. One may think, there are many roads to Rome; however, an important point is that the various metals have distinct strengths in terms of selectivity and activity for chemical CO₂ utilization. The behavior of these different metals in CO₂ conversion can further be modulated through introduction of different ligands.