Number the following bicycles

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{button-white}Solution{/button-blank}

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One of the bridgeheads is
given locator 1 medium size and ends in small. 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



b) The 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



c) Bicyclo 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




d) Bicyclo with three chains of equal length.

We start from the bridgehead carbon closest to fluorine. Name: 2 -Fluorobicyclo[2.2.2]octane