When it comes to trapping carbon dioxide to reduce industrial greenhouse gas emissions, the biggest challenge is finding something to do with the CO2. One chemical approach is to insert CO2 into epoxides to form cyclic carbonates, which in turn can be used as solvents, as battery electrolytes, and to make polycarbonate plastics. However, the reaction usually requires high temperature and pressure. A team led by Omar K. Farha and Joseph T. Hupp of Northwestern University has developed a hafnium-based metal-organic framework (MOF) catalyst for the process that works under ambient conditions (J. Am. Chem. Soc. 2014, DOI: 10.1021/ja508626n). The researchers found that hafnium forms stronger metal-oxygen bonds in MOFs compared with other metals and thus is a stronger Brønsted acid and an optimal catalyst. In a separate development, Anita E. Mattson’s group at Ohio State University reports using silanediols to catalyze CO2 insertion into epoxides under ambient conditions (ChemSusChem 2014, DOI: 10.1002/cssc.201402783). Silanediols are noncovalent organocatalysts codiscovered by Mattson’s group that mediate a range of chemical reactions by coupling reaction partners through hydrogen-bonding interactions.