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Ignoring whether or not this molecule could exist, is there a name for this type of chirality? This molecule's mirror image cannot be superimposed on itself but there are no chiral centres.

Chiral boron compound

Even though the bottom boron only has three substituents, the fact that they are all joined at the top gives it similar geometrical properties as if it were tetrahedral.

The InchI is InChI=1S/C4H8B2OS/c1-2-6-7-3-5(1)4-8-6/h1-4H2

Mithoron
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hazza_h
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  • Could it be an example of Axial Chirality? Where the axis is through the boron atoms? – user137 Sep 15 '20 at 15:18
  • how would boron exist in bridge head position? Is there a point in discussing chirality for something that may not even exist? – Safdar Faisal Sep 15 '20 at 15:20
  • @safdar I'm sure you could substitute the atoms for something that could exist instead. I chose boron instead of carbon because trigonal planar atoms are inherently not stereocenters. The geometry is what matters. – hazza_h Sep 15 '20 at 15:27
  • Something like this? https://chemistry.stackexchange.com/questions/136695/r-s-configuration-of-bridging-carbon-in-bicyclic-system – Safdar Faisal Sep 15 '20 at 15:54
  • This atom's environment wouldn't be trigonal planar - pyramidalisation with ring strain. Still it's planar chirality. – Mithoron Sep 15 '20 at 16:08
  • https://chemistry.stackexchange.com/questions/35470/why-is-trans-cyclooctene-chiral – Mithoron Sep 15 '20 at 17:22
  • You don't need atoms or bonds to define chirality. Just the colored balls will suffice. I think it is an example closer to planar chirality: P or Rp. (C-C-B-S). http://ursula.chem.yale.edu/~chem220/chem220js/STUDYAIDS/isomers/RS14272/planar.html – user55119 Sep 15 '20 at 19:11
  • About "but there are no chiral centres" : not clear if you are aware, but they are not needed for a molecule to be chiral. – Alchimista Sep 16 '20 at 07:00

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