How can I name this organic compound while adhering to the IUPAC standards?

A name could not be generated for this structure.

  • 27
    $\begingroup$ Congratulations! This structure breaks my favorite structure editor (ChemDoodle) when I attempt to have it name this molecule... $\endgroup$
    – Curt F.
    Feb 16, 2016 at 14:07
  • 16
    $\begingroup$ Congratulations, this structure breaks ChemDraw's structure-to-name feature too! I'll try LexiChem when I'm at work tomorrow. $\endgroup$ Feb 16, 2016 at 16:11
  • 10
    $\begingroup$ I can't even search chemspider with the skeleton (non-aromatic rings) with similarity search (tanimoto 99%) - I get an error. This is the devil's own structure... $\endgroup$
    – gilleain
    Feb 16, 2016 at 16:31
  • 8
    $\begingroup$ The preferred systematic name in phane nomenclature for the outer ring (without the “1,4-phenylene” bridge) is “1,3,5,7(1,2),2,4,6,8(1,4)-octabenzenacyclooctaphane”. By way of comparison, the similar [8]cycloparaphenylene with the systematic name “1,2,3,4,5,6,7,8(1,4)-octabenzenacyclooctaphane” is described in dx.doi.org/10.1039/c2sc20719b. $\endgroup$
    – user7951
    Feb 16, 2016 at 17:22
  • 17
    $\begingroup$ I actually suggest issuing this as a Twitter challenge to ChemDraw, OpenEye, ChemDoodle, ACD, etc. $\endgroup$ Feb 17, 2016 at 16:59

2 Answers 2


It indeed can be named quite nicely using the recent "phane" nomenclature from the Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013, here is the example*

sample schema with structures and names

By abstracting to the bicyclo phane composed of nine benzene nodes ("superatoms") of three kinds, we get

schema with structures


Note that the "superatom" (more precise "amplificant") locant ordering matters. If the numbers in the first parentheses were sorted, it would mean a different structure, that is little bit hard to draw in 2D:

srtucture for the obsolete answer


Publicly accessible references:

*) Please note there is a mistake in the example from the book, the pyridine (4) has wrong internal ring numbering - 4 should be replaced with 5. The name is correct, though. (It is mentioned in errata, for page 310).

  • $\begingroup$ "[3.3.1] " What does it stand for? $\endgroup$ Apr 29, 2017 at 6:54
  • $\begingroup$ @Mockingbird, "[3.3.1]" describes that the skeleton composed of two cycles (bicyclo) has three branches (that each begin and end in two distinct nodes - it is always the case; here they are X) (therefore three dot-separated numbers) that have 3, 3 (two identical (X)YZY(X) branches) and 1 ((X)Y(X) branch) nodes ("superatoms") respectively, excluding the X end points, total 9 (nonaphane). This type of naming is also used for hydrocarbons, etc. If X, Y and Z were just carbon atom (with hydrogens), it would be bicyclo[3.3.1]nonane. $\endgroup$
    – mykhal
    Apr 29, 2017 at 7:46
  • $\begingroup$ @mykkhal what if there are substituents? Like Cl or Br joined to one molecule. $\endgroup$ Apr 30, 2017 at 13:12
  • $\begingroup$ @Mockingbird, numbering is done by indicating the number of the "superatom" and the position on it as upper index, so this structure with chlorine on all peripheral positions would be 1⁴,1⁵,1⁶,2²,2³,3³,3⁴,3⁵,3⁶,4²,4³,5⁴,5⁵,5⁶,6²,6³,7³,7⁴,7⁵,7⁶,‌​8²,8³-docosachloro-1‌​,5(1,3,2),2,4,6,8,9(‌​1,4),3,7(1,2)-nonabe‌​nzenabicyclo[3.3.1]n‌​onaphane $\endgroup$
    – mykhal
    May 9, 2017 at 21:45
  • $\begingroup$ "Note that the "superatom" (more precise "amplificant") locant ordering matters. If the numbers in the first parentheses were sorted, it would mean a different structure, that is little bit hard to draw in 2D" Does it only matter for the superatoms by which the "[3.3.1]" is specified? $\endgroup$ May 10, 2017 at 3:51

ChemDoodle 8 can name this via the extended von Baeyer system, although the name is quite long. Thanks for putting up this nice example though!

von Baeyer name


  • 9
    $\begingroup$ Although impressive, the name ignores the identity of benzenes and treats the compound as poly-alekene. $\endgroup$
    – ssavec
    Feb 17, 2016 at 20:13
  • 2
    $\begingroup$ Interesting, Marvin Sketch seems to agree with ChemDoodle and Chem Office can not generate a name at all. $\endgroup$
    – HCSthe2nd
    Feb 24, 2016 at 16:39

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