Solvents used in catalysis can be broadly categorized into several types:
Protic Solvents: These solvents can donate a hydrogen bond and include water, alcohols, and carboxylic acids. They are often used in reactions where stabilization of charged intermediates is necessary. Aprotic Solvents: These solvents do not donate hydrogen bonds and include acetone, acetonitrile, and dimethyl sulfoxide (DMSO). They are suitable for reactions where polar but non-protic environments are required. Ionic Liquids: These are salts in a liquid state at room temperature and are used for their unique properties such as low volatility and high thermal stability. Supercritical Fluids: These are substances at conditions above their critical temperature and pressure, combining properties of both liquids and gases. Supercritical CO2 is a common example used in green chemistry.
