[Alexander]

is it possible to separate cis- and trans- isomers of diazo compounds using thin layer chromatography (silufol plates).

[ARGOS++]

Dear Alexander,


Of course You can,  — if  ….. .

As you know,  FREE rotation around a double-bound is “impossible”, so
it depends ?ONLY? on a “three parameter combination” :
   A.)  The kind of your Thin-Layer/?Paper?.
   B.)  The length of your Thin-Layer.
   C.)  The mixture of your Eluent.

Of course, - exact the same -, it’s as more easy as both R_i are different.

Good Luck!
                      ARGOS⁺⁺

[movies]

The diazo moiety is linear; there are no cis/trans isomers.

[ARGOS++]

Dear movies,

I would like to answer such Questions in the same manner and efficiency as you do.

IF your postulate holds, Then I believe You are generating quite a few problems for
several scientists of organic/physical-organic Chemistry.

To use a simple Example first:
     Mr. Manfred Hesse; Mr. Herbert Meier; and Mr Bernd Zeeh, report in their
     Book: “Spectroscopic Methods for organic Chemistry” (5^th Edition; 1^st Edition: 1979)
     in Chapter about N¹⁵ NMR chemical Shifts for:
       (E)-Azobenzene    in CHCl3        of:     N1, N2  = +129.0
       (Z)-Azobenzene    in CHCl3        of:     N1, N2  = +146.5
       (E)-Azoxybenzene    in CHCl3     of:     N1 =           -57.1   N2  =  -46.7
       (Z)-Azoxybenzene    in CHCl3     of:     N1 =           -36.0   N2  =  -19.8

Maybe you can tell me that I’m wrong in this case, as I all times meant, that (E)/(Z) are
only older/newer Structure-Naming-Conventions for the same as cis-/trans- is standing.

On the other side, I know from several scientists, who report, to have formed
Metal Complexes of the following general Form: (n = 3 or 4)
                                                                                    ____                             _____     
                                    _____                                      |                              ____       |
                                   /                                              |                             /              |
                         _____/                                                |                 ______/               |
                        /         \           /                                   |                /           \              |
         _{H – O} ___/           \_____/                                    |     _O ____/             \_____/   |
                        \          /                                              |    /           \           /              |
  n  *                 \_____/            +  Meⁿ⁺   --->  Meⁿ⁺  |                  \_____/               |
                         /                                                        |                  /                         |
                 _     /                                                         |      \         /                           |
                 N==N                                                         |       N==N                             |
                /                                                                 |      /                                     |
               /                                                                  |     /                                      |
              R1                                                                 |    R1                                     |
                                                                                   |___                                 ___| n
(Sorry for my painting. I hope you will see it anyway clear! 
  The Rings should be identified as of Bencene nature.)
The correct Electron-Balancing is left to you, because it’s a “hard” job to incorporate it into this picture.
Unfortunately I was not very interested in Complex Chemistry at that time when
they have presented their work, so I didn’t caught the Literature Citation for them, and
at the moment I’m missing the search possibility for it, too.

With a “linear” postulate, such could not be thought possible, without involving quite a lot of Energy!

I would like if you can bring these discrepancies to a good end.
Good Luck!
                    ARGOS⁺⁺

[Sam (NG)]

Dear movies,

I would like to answer such Questions in the same manner and efficiency as you do.

IF your postulate holds, Then I believe You are generating quite a few problems for
several scientists of organic/physical-organic Chemistry.

To use a simple Example first:
     Mr. Manfred Hesse; Mr. Herbert Meier; and Mr Bernd Zeeh, report in their
     Book: “Spectroscopic Methods for organic Chemistry” (5^th Edition; 1^st Edition: 1979)
     in Chapter about N¹⁵ NMR chemical Shifts for:
       (E)-Azobenzene    in CHCl3        of:     N1, N2  = +129.0
       (Z)-Azobenzene    in CHCl3        of:     N1, N2  = +146.5
       (E)-Azoxybenzene    in CHCl3     of:     N1 =           -57.1   N2  =  -46.7
       (Z)-Azoxybenzene    in CHCl3     of:     N1 =           -36.0   N2  =  -19.8

There is a difference between Azo and diazo compounds:

[Alexander]

this is a mismatch in terminology. if everyone understood what I mean in diazo compound, I don't see any problems here

[lavoisier]

Of course there is a problem here!

Nomenclature exists for the very reason that we want to avoid such misunderstandings. You're not supposed (or allowed) to change it and still expect people to understand you. It's the basis of scientific communication.

If you write 'diazo' compound, it is R-C(N2)-R', and of course it has no cis or trans isomers as such.
If you write 'azo' compound, it is the nitrogen analogue of an alkene R-N=N-R', and it does have stereoisomers (more or less stable, but it does).

[ARGOS++]

Dear Sam(UoN), Dear lavoisier,

Of course:
        I absolutely AND  uncompromisingly AGREE with You!

Dear Alexander, Thank you very much for your try of support and protection!

But I believe:
          A Mistake IS a Mistake, and therefore has to be left as what it is:
                                  A Mistake  ?  in any Case!!

Yes, I guided myself by the terms cis- and trans- isomers, and did not any other proof.
Additionally I translated all to German (Sorry that language is closer to my mother tongue) for thinking.
Maybe I’m also already too much stamped by the “production slang” for this kind of products, where
everybody “knows?” exactly what “the other” means/tries to tell.

Quintessence:
       Dear movies, The proof holds!, You are absolutely right,  - sorry!


Thank you lavoisier, for spending the "good end".
Good Luck!  ? Till my next, I hope very, very rarely Mistake!
                     ARGOS⁺⁺

P.S.:    Sorry for my “abstinence” during several days, but I had nearly not one chance to be “on Air”!

[lavoisier]

Actually, Argos++, I was answering Alexander when I wrote that there was a problem. I wasn't referring to your contribute, which, I believe, was correct in its own right.
I was pointing out the importance of certain standards and conventions in scientific communication, and (admittedly) I was a little irritated by a statement sounding like 'as long as people understand what I mean, I can use whatever terms I like'.

By the way, I know it was just a mistake, and I wasn't that harsh... I didn't ask for anybody's head, did I?  ;-)

[ARGOS++]

Dear lavoisier,

You did NOT, of course    ??   AND I offered “it” NOT, of course !!

But you donated the “ good end ”,   ?? as I told!
Thank You.

Good Luck!
                    ARGOS⁺⁺