Water-sensitive, solution-phase catalysts can be protected from unwanted hydrolysis by anchoring them inside highly hydrophobic porous organic polymers, according to a study (Chem 2016, DOI: 10.1016/j.chempr.2016.09.008). Enveloping the catalytic sites in a water-excluding polymeric framework can extend catalyst lifetime as well as broaden the range of reactions for which they can be used. Shengqian Ma of the University of South Florida and coworkers demonstrated the strategy by synthesizing rhodium-infused phosphite-based materials and testing how well they catalyze conversion of olefins to aldehydes, a commercially important reaction. Rhodium phosphite catalysts generally are very active but are prone to decomposition via hydrolysis of P–O bonds. To make a superhydrophobic version of the phosphite-based material, the team prepared a substituted triphenyl phosphite monomer and polymerized it. The researchers treated the water-repellent porous polymer with a rhodium precatalyst, resulting in the rhodium binding to the phosphite sites within the material. Catalysis tests showed that the superhydrophobic material was highly active, even in the presence of water, retaining its activity throughout 14 runs over a weeklong period. In contrast, the activity of traditional heterogeneous and homogeneous rhodium catalysts tested began falling after just a few runs.