Hello Candidate,

This type of isomerism arises due to the presence of different alkyl chains on each side of the functional group. It is a rare type of isomerism and is generally limited to molecules that contain a polyvalent atom such as sulfur, oxygen, nitrogen etc. surrounded by alkyl groups.

To find this type of isomerism, just see the no. of carbon atoms present on each side of polyvalent atom.

Hope it helps.