Assessment of the Sustainability of Fluorous Compounds with Short-Chain Perfluoroalkyl Groups 

Perfluoroalkanes, perfluorodialkyl ethers, and perfluorotrialkyl amines readily form liquid-liquid biphasic systems even with simple organic molecules, which have been the foundation of fluorous synthesis, catalysis, analytical methods and other chemical and biomedical applications. Fluorous molecules and the surfaces of fluorous materials are considered hydrophobic, which repel water and less polar molecules and materials. In general, the attachment of non-polar fluorous substituents, in appropriate size and numbers, to polar molecules and the surfaces of polar materials can decrease their polarity; even superhydrophobicity can be achieved. The phase-out of long-chain perfluoroalkyl substances due to their adverse environmental and health effects have generated considerable interests of their replacement. The combined use of short-chain perfluoroalkyl groups could preserve the hydrophobic properties and potentially lower their toxicity. Therefore, a wide range of novel fluorous compounds with short-chain perfluoroalkyl groups, including iodides, alcohols, thiols, silanes, bipyridines, and pincer ligands will be synthesized and characterized. They can be used as fluorous catalysts and or reagents for surface modifications. In parallel, their toxicity will be investigated and compared with perfluoroalkyl carboxylic acids to assess their sustainability.