Editing Basic aromatic ring

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{| border="0" cellpadding="5" cellspacing="0" style="margin: 1em; float: right;" class="wikitable"
! colspan="3" | Basic aromatic ring systems
|- align="center" valign="bottom"
| [[Image:Pyridine structure.png|70px]]<br>[[Pyridine]]
| [[Image:Quinoline structure.png|120px]]<br>[[Quinoline]]
| [[Image:Acridin.svg|170px]]<br>[[Acridine]]
|- align="center" valign="bottom"
| [[Image:Pyrazine structure.png|70px]]<br>[[Pyrazine]]
| [[Image:Quinoxaline structure.png|120px]]<br>[[Quinoxaline]]
| [[Image:Phenazine.png|170px]]<br>[[Phenazine]]
|- align="center" valign="bottom"
| [[Image:Imidazole structure.png|70px]]<br>[[Imidazole]]
| [[Image:Benzimidazole structure.png|120px]]<br>[[Benzimidazole]]
| [[Image:Purine structure.png|120px]]<br>[[Purine]]
|- align="center" valign="bottom"
| [[Image:Pyrimidine structure.png|70px]]<br>[[Pyrimidine]]
| [[Image:Quinazoline structure.png|120px]]<br>[[Quinazoline]]
| [[Image:Pteridin - Pteridine.svg|120px]]<br>[[Pteridine]]
|- align="center" valign="bottom"
| [[Image:Pyrazole structure.png|70px]]<br>[[Pyrazole]]
| [[Image:Indazol.svg|120px]]<br>[[Indazole]]
| &nbsp;
|- align="center" valign="bottom"
| [[Image:Pyridazine structure.png|70px]]<br>[[Pyridazine]]
| [[Image:Cinnoline structure.png|120px]]<br>[[Cinnoline]]
| &nbsp;
|}

'''Basic aromatic rings''' are [[simple aromatic ring|aromatic rings]] in which the [[lone pair]] of [[electron]]s of a ring-[[nitrogen]] [[atom]] is not part of the [[aromatic]] system and extends in the plane of the ring.  This lone pair is responsible for the [[Base (chemistry)|basicity]] of these [[nitrogenous base]]s, similar to the nitrogen atom in [[amine]]s.   In these compounds the nitrogen atom is not connected to a [[hydrogen]] atom. Basic aromatic compounds get [[Protonation|protonated]] and form aromatic [[cation]]s (e.g. [[pyridinium]]) under [[acid]]ic conditions.   Typical examples of basic aromatic rings are [[pyridine]] or [[quinoline]].  Several rings contain basic as well as non-basic nitrogen atoms, e.g. [[imidazole]] and [[purine]].

In non-basic aromatic rings the [[lone pair]] of [[electron]]s of the nitrogen atom is delocalized and contributes to the aromatic [[pi electron]] system. In these compounds the nitrogen atom is connected to a [[hydrogen]] atom. Examples of non-basic nitrogen-containing aromatic rings are [[pyrrole]] and [[indole]]. Pyrrole contains a lone pair that is part of the pi-conjugated system, so it is not available to deprotonate an acidic proton.<ref>{{Cite web |last=teachthemechanism |date=2013-03-12 |title=Lone Pairs and Aromaticity |url=https://teachthemechanism.com/2013/03/12/lone-pairs-and-aromaticity/ |access-date=2023-03-11 |website=Teach the Mechanism |language=en-US}}</ref>

The basic aromatic rings [[purine]]s and [[pyrimidine]]s are [[nucleobases]] found in [[DNA]] and [[RNA]].

== References ==
{{Reflist}}

==See also==
* [[Simple aromatic ring]]

{{DEFAULTSORT:Basic Aromatic Ring}}
[[Category:Nitrogen heterocycles]]