how can we write nomenclature of bi cyclic compunds?

Question

organic chemistry

Answer 1

There are more than one method. The IUPAC nomenclature system is the most commonly used one. Check out the sites below:

Answer 2

You count the Carbons on the bigger ring first. Then the second ring. Lastly you count the bridge Carbons. You place them in brackets as follows: bicyclo [#C in larger ring.#C in smaller ring.#C in bridge] common name.
For bicyclo[4.3.0]nonane, you'd have a pentane ring attached to a hexane ring.
It's easier if you can see pictures:
http://www.chemistry.mcmaster.ca/courses/2oa3/lecture_two.pdf#search='naming%20bicycloalkane'
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