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Is there a way to draw the aromatic "horseshoe" (forgot the official name) structure of a protonated benzene cation (arenium) with ChemDraw, and not the cation with double bonds?

benzenium

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    $\begingroup$ I've added an image produced with chemfig to illustrate your question — hopefully it reflects your point. If not, feel free to add your own image instead:) $\endgroup$ – andselisk Mar 27 '19 at 12:53
  • $\begingroup$ It's called Arenium ion. en.wikipedia.org/wiki/Arenium_ion $\endgroup$ – KingLogic Oct 19 at 16:19
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Draw cyclohexane. Open Drawing Elements. Select 270o circle. Orient with lasso and adjust size. Insert in cyclohexane. Add H's and +.

enter image description here

ADDENDUM: For a centered structure. Draw cyclohexane, arc and + inside each other. Select them. Go to Object>align. Select L/R centered then T/B centered. Add hydrogens. See also Comments. PS: Clearly, ChemDraw does not recognize the structure as protonated benzene. Can't have everything ;).

enter image description here

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  • $\begingroup$ Interesting, this is exactly what I had in mind. What prevented me from writing an answer is that this way the charge is treated by ChemDraw as the stray one, and the entire molecule is recognized as cyclohexane if one would try to generate its name (Alt+Ctrl+N). Also, what bugs me is that vertical alignment tool doesn't work nicely for arcs, so it cannot be perfectly centered within the ring. Are you aware of any means to overcome all those issues? $\endgroup$ – andselisk Mar 27 '19 at 15:34
  • $\begingroup$ CD13 or 17 cannot handle "Structure to Name". But that wasn't the question. On an Apple laptop I had no problem (CD13) with orienting the arc or reducing its size. I hope I understood you correctly. $\endgroup$ – user55119 Mar 27 '19 at 15:44
  • $\begingroup$ @andselisk: About centering.. Draw ring, arc and + inside each other. Select them. Go to Object>align. Select L/R centered then T/B centered. $\endgroup$ – user55119 Mar 27 '19 at 15:53
  • $\begingroup$ CD18 on Windows can generate a name, but, as I said, it's cyclohexane and is wrong. As for alignment, that's exactly what I did, but it looks like the cut edge is used for alignment of arcs, not the circumference, which drives my internal perfectionist nuts:) (my screenshot) But you are right, that's nitpicking and not what OP asked, and the proposed method helps drawing something that is close enough, so +1. $\endgroup$ – andselisk Mar 27 '19 at 15:54
  • $\begingroup$ @andselisk: I was able to make a centered structure that now reads cyclohexane. How do you put a screen shot in comments? $\endgroup$ – user55119 Mar 27 '19 at 16:04
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That is a terrible way of drawing that intermediate. You should draw a cyclohexane, then right-click on the four bonds where the delocalization takes place and choose double -> tautomeric.benzenium

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    $\begingroup$ Welcome to ChemSE. @andselisk was asking for a way to draw the structure he provided. He did not ask for the "best" way to do it. We strive to be a kind and caring community. " Here is an alternative way of drawing that intermediate" would have been a more civil statement. You may wish to consider an edit. chemistry.stackexchange.com/conduct $\endgroup$ – user55119 Oct 19 at 17:55
  • $\begingroup$ @user55119 I didn't ask the question, Cloud Chem did:) I only added an illustration to what is commonly shown in the literature as a "horseshoe benzene". Despite the main part of the post being critics, I think it is still a valid alternative answer. $\endgroup$ – andselisk Oct 19 at 18:59
  • $\begingroup$ @andselisk: My mistake. I still stand by the rest of my Comment. $\endgroup$ – user55119 Oct 19 at 19:25

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