Isn't 1,6-dibromo cyclohexene same as 2,3-dibromo cyclohexene? If yes, then why do they have different names? The figure is :

Dear Student,

According to preference rule double bond must have lowest number as compared to substituent (halogen). So, numbering of above mention compound is done in the given below manner.



1,6- Dibromocyclohexene is incorrect and is different from 2,3 _ Dibromocyclohexene.

Regards