# Is there a characterisation for conjugated dienes similar to cis-trans?

As shown above,we know there are two configurations possible for conjugated dienes.

Are they given any special names like we have cis and trans? This came up because while studying the Diels Alder reaction, it occured to me that maybe only the 'cis' like dienes will go through the reaction.

• Go through $E -Z$ nomenclature. Here it is not possible ,but in any double bonds where the attached groups on one side is different, that is very useful. – Soumik Das Mar 14 '18 at 18:36
• Yes, the terms "s-cis" (single bond cis) and "s-trans" (single bond trans) are often used to describe the geometrical relationship of the double bonds attached to the central single bond. See [this earlier answer]( chemistry.stackexchange.com/questions/44053/…) for more information as well as how those conformations affect the Diels-Alder reaction. – ron Mar 14 '18 at 18:54