what are cyclic isomers.. please explain in detail..?

I found doc's answer confusing. Consider hexene: HC=CHCH2CH2CH2CH3 You can change the position of the C=C (1→3) and make the C-C-C chain branched, but we want cyclic isomers.

The first isomer is an extremely common cmpd cyclohexane (CH2)6 which is a six membered ring

http://en.wikipedia.org/wiki/Cyclohexane

But it doesn't stop there! We can have a five membered cyclopentane ring with a methyl substituent:

CH3C5H9 http://en.wikipedia.org/wiki/Methylcyclopentane (present in the Mn antiknock agent)

only one isomer.

Next are the cyclobutane derivs dimethycyclobutane (CH3)2(C4H7) (1,1; 1,2 cis and trans, trans is chiral, 1,3)

http://www.mychemistrytutor.com/forums/organic-che...

Then we can have ethylcyclobutane (C2H5C4H7):

http://www.chemicalbook.com/ProductChemicalPropert...

I would do the cyclopropane dervs with a C3 ring but my brain has overheated. I'll leave you to work them out.

Cyclic Isomers

Cyclic compounds are those that are composed of one or more rings. Isomers have the same number of each type of atom per molecule, in the broadest sense of the word. So dimethyl ether CH3OCH3 and C2H5OH, both have 2 carbons, 6 hydrogens and 1 oxygen atom per molecule. There are other types of isomers that differ in the placement of groups about a double bond. These are called geometrical isomers. There are also those that are non-superposable mirror images of each other and these are known as optical isomers (because each form rotates plane polarized light in a different direction). So if I combine both isomeric compounds with a ring structure of got two cyclic isomers. An example would be the compounds azulene and naphthalene. The former has two fused rings- one with five carbons and the other with seven carbons and is intense blue in color.

The other is colorless and consists of two fused six-membered rings. But both compounds are C10H8 and have alternating single and double bonds between C atoms..