Which of the following reactions do square planar complexes undergo?

#a)# oxidative addition
#b)# substitution
#c)# ligand dissociation
#d)# migratory insertion

1 Answer
Aug 14, 2017

If the transition metal has a low oxidation state, the square planar complex generally undergoes oxidative addition, as it is easy to oxidize a metal with a low oxidation state.


Square planar complexes generally only undergo:

  • oxidative addition reactions to form higher-coordinate complexes (octahedral products are common), if the oxidation state of the central metal is low.

For example:

Inorganic Chemistry, Miessler et al., pg. 545

  • substitution reactions under an associative interchange mechanism, #I_a#, if the oxidation state of the central metal is not low.

For example:

Inorganic Chemistry, Miessler et al., pg. 461


On the other hand...

  • ligand dissociation tends to occur in complexes that are 5- or 6-coordinate, though it is possible for it to be an intermediate step in a longer reaction.

For example:

Inorganic Chemistry, Miessler et al., pg. 541

  • migratory insertion generally occurs in complexes where ligands are cis to each other, often seen in octahedral complexes.

For example:

Inorganic Chemistry, Miessler et al., pg. 552

  • reductive elimination is generally seen in 5- or 6-coordinate complexes with central metals of high oxidation states.

For example:

Inorganic Chemistry, Miessler et al., pg. 547