February 25, 2021, 08:28:55 AM
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Topic: How can someone identify cis and trans here?  (Read 1529 times)

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Offline Borek

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Re: How can someone identify cis and trans here?
« Reply #15 on: December 29, 2019, 04:46:02 AM »
  (1) You copied and pasted a 1996 "unauthenticated" something and a 1993 publication
        by Blackwell publications that calls itself a "guide" and refers to the IUPAC rules and
        states that E/Z has largely replaced cis / trans.  I'm not arguing with that.

Quote comes from the very Blackwell publication, "unauthenthicated" probably refers just to the legal status of the document (which is not something I selected randomly, it is linked to from the IUPAC site itself).

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P-92.1.2 states that CIP rules are used to prioritize a,b,c,d

That would be a game changer. Sadly, I have no access to the book, and the only thing I can check is the IUPAC Provisional recommendations which says nothing about using CIP for cis/trans (to make things more difficult it also uses different, and occasionally erroneous, numeration of subpoints).

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IUPAC isn't always consistent

is a thing I can easily agree on.

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Offline MNIO

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Re: How can someone identify cis and trans here?
« Reply #16 on: December 29, 2019, 05:23:36 PM »
I go back to my last point.  There is world full of people currently using cis/trans for double bonds with 3 and 4 ligands.  Clearly you can't argue with that right?  And they are prioritizing the groups when determining cis/trans.  Non-arguable.  And clearly even IUPAC is using cis and trans for 3 ligands.  I showed you an image right from their organic chemistry nomenclature rules. 

So.... clearly, I'm not making this up am I?

Offline MNIO

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Re: How can someone identify cis and trans here?
« Reply #17 on: December 29, 2019, 11:14:00 PM »
this is my last post on this topic.  it's been thoroughly argued.  From the IUPAC blue book 2013 page

and

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