Number the following bicyclic compounds.

SOLUTION:

Molecule 1.

Locator 1 is given to one of the bridgeheads and the longest chain continues to be numbered until reaching the other bridgehead, the numbering continues with the medium-sized chain and ends with the small one.
The choice of the bridging carbon to which we give localizer 1 is conditioned to the fact that the substituents take the smallest possible localizers. In this example, the bottom bridging carbon should be given locant 1, so methyl will have locant 2. If we give locator 1 to the carbon bridge above, the methyl will occupy position 4, higher and therefore incorrect.

Name: 2-Methylbicyclo[3.1.0]hexane

Molecule 2.

Numbering begins at the bridgehead carbon and the longest chain (3 carbons) is numbered. The second bridgehead takes locator 5 and from there we continue numbering the median chain. Numbering starts at the top bridging carbon so that chlorine takes the lowest locant.

Name: 6-Chlorobicyclo[3.2.0]heptane

Molecule 3.

Bicyclic compound with chains of 3.2 and 1 carbons. We begin the numbering with the bridgehead carbon closest to the bromine. We number large chain, medium chain and finally the bridge (position 8 ).

Name: 2-Bromobicyclo[3.2.1]octane

Molecule 4.


Bicycle with three chains of equal length. We start from the bridgehead carbon closest to fluorine.

Name: 2-Fluorobicyclo[2.2.2]octane