stereosõltuvus

Stereosõltuvus, also known as stereoselectivity or stereospecificity, refers to the preference of a chemical reaction to produce one stereoisomer over another. This phenomenon is crucial in organic chemistry and the synthesis of complex molecules, particularly in pharmaceuticals, where different stereoisomers can have vastly different biological activities. A reaction is considered stereoselective if it yields a mixture of stereoisomers, but with one or more isomers predominating over others. This preference can be influenced by various factors, including the structure of the reactants, the reaction conditions, and the presence of catalysts.

Stereospecificity is a more stringent form of stereoselectivity. In a stereospecific reaction, a particular stereoisomer of the reactant will exclusively or predominantly yield a specific stereoisomer of the product. This means that if you start with a different stereoisomer of the reactant, you will obtain a different stereoisomer of the product. For example, an addition reaction across a double bond might be stereospecific, meaning that a cis-alkene gives a different stereoisomer of the product compared to a trans-alkene. Understanding and controlling stereoselectivity and stereospecificity are key challenges in modern chemical synthesis, enabling the precise construction of molecules with desired three-dimensional arrangements.