PERICYCLIC REACTION Meaning and
Definition
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A pericyclic reaction refers to a type of organic chemical reaction that involves the redistribution of bonding electrons in cyclic systems. It occurs through a concerted process, meaning that all the bond-making and bond-breaking steps occur simultaneously, without the intermediacy of any reaction intermediates or charged species. Pericyclic reactions are often characterized by their stereospecificity, regioselectivity, and high degree of orbital symmetry, which govern the reaction outcome.
These reactions are governed by the principle of orbital symmetry, which states that for the reaction to occur, the symmetry of the molecular orbitals involved must match the symmetry of the transition state. Common examples of pericyclic reactions include cycloadditions, electrocyclizations, sigmatropic rearrangements, and group transfer reactions.
Pericyclic reactions have found significant applications in synthetic organic chemistry as they offer efficient and regiocontrolled access to complex molecular structures. They are widely used for the construction of natural products, medicinal compounds, and functional materials due to their ability to generate multiple rings and stereocenters in a single step.
The study of pericyclic reactions has advanced our understanding of reaction mechanisms and has significant implications in the design and development of new synthetic strategies. It has also provided valuable insights into the nature of chemical bonding and the influence of orbital interactions on reaction selectivity and efficiency.
Etymology of PERICYCLIC REACTION
The word "pericyclic" is derived from the Greek words "peri" meaning "around" and "kyklos" meaning "circle" or "cycle". "Reaction" refers to the chemical process or transformation.
