insertion

  1. A chemical reaction or transformation of the general type:
    I03058-1
    in which the connecting atom or group Y replaces the bond joining the parts X and Z of the reactant XZ. An example is the carbene insertion reaction:
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    The reverse of an insertion is called an extrusion.
    See also: α-addition
    Source:
    PAC, 1994, 66, 1077 (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1125
  2. A general term given to a reaction involving the transfer of a guest atom, ion or molecule into a host crystal lattice.
    Source:
    PAC, 1994, 66, 577 (Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)) on page 583