Lewis acids are commonly defined as an electron pair acceptor, but such a definition seems to diminish their importance in organic synthesis. These species are highly useful in synthetic chemistry due to their ability to coordinate with carbonyl groups and other oxygen- and nitrogen-containing functional groups. Many Lewis acids can even be used in catalytic amounts to effect various transformations.
Sigma-Aldrich is pleased to provide a diverse array of hard and soft Lewis acids from the traditional titanium tetrachloride and boron trifluoride to Montmorillonite powders. For more Lewis acids, check the Catalysis section of our online product catalog for any catalytically useful Lewis acids.