There are various types of reactions of metals coordination complexes. These can be described as association and dissociation, substitutionoxidation and reduction, insertion and elimination, and oxidative addition and reductive elimination.

This page aims to categorise each of the above reaction types, and list how the total number of electrons in the complex, the oxidation state of the metal and its d-electron count change over the course of the process. An example of each reaction type is also given.

Association and Dissociation

Electron Number (EN) p (eg. 16) p+2 (eg. 18)
Oxidation State (OS) x x
d-electron number (DN) n n

Substitution

EN p p
OS x x
DN n n
Oxidation and Reduction
EN p (eg. 19) p-1 (eg. 18)
OS x x
DN n n
Insertion and Elimination
EN p p
OS x x
DN n n
Oxidative Addition and Reductive Elimination
EN p (eg. 16) p+2 (eg. 18)
OS x x+2
DN n n-2
Square-planar d8, 16e goes to octahedral 18e.