Complexhydridit

Complexhydride is a term used in chemistry to describe chemical compounds containing a complex anion in which a metal atom is covalently bonded to one or more hydride ions. These compounds are typically strong reducing agents, meaning they readily donate electrons in chemical reactions. The hydride ion (H-) is a powerful nucleophile and can participate in a variety of reactions, including the reduction of carbonyl groups, esters, and carboxylic acids.

Common examples of complex hydrides include lithium aluminum hydride (LiAlH4) and sodium borohydride (NaBH4). Lithium aluminum hydride is a very strong reducing agent and can reduce a wide range of functional groups. Sodium borohydride is a milder reducing agent, typically used for the reduction of aldehydes and ketones. The reactivity of a complex hydride depends on the nature of the metal cation and the ligands surrounding the central metal atom.

Complex hydrides are often prepared by reacting metal hydrides with other metal halides or by electrochemical methods. They are usually air and moisture sensitive and must be handled with care, often under an inert atmosphere. Their utility in organic synthesis as selective reducing agents makes them indispensable tools in the laboratory and in industrial processes. The choice of complex hydride for a particular reaction depends on the desired selectivity and the functional groups present in the substrate.