N violations of octet rule

User 870ab5b546

10-03-2010 21:09:50

I would like an option to set Marvin (both the GUI and through the API) to treat hypervalent N as having a valence error.


Currently, Marvin does not recognize O=[N-](=O)=O as having a valence error, even though it has a total electron count of 12 electrons.


Also, Marvin is teaching my students the bad habit of drawing nitro groups with a pentavalent N.

ChemAxon 990acf0dec

11-03-2010 11:47:50

Hi Bob,


Regarding the hipervalent N valence error, please see my comment in the related topic (https://www.chemaxon.com/forum/viewpost27722.html#27722).


The other issue, i.e. whether a valence error should be shown for nitro compounds where both oxygens are connected with double bond to the nitrogen is not an easy decision, because although in teaching it would be nice, many structures had been drawn this way in the past (not in Marvin!), and for those users who still need to handle these structures it would be very inconvenient.


Best regards,


Akos

User 870ab5b546

11-03-2010 13:57:58

You could create a flag, "allowPentavalentN", and set its default to true.  It should be one of the MarvinSketch parameters, as well as controllable from the GUI and API.

ChemAxon 7c2d26e5cf

19-03-2010 16:02:13

Hi Bob,


Akos is on sick leave.


He will answer as he returned.


Tamas

ChemAxon 990acf0dec

24-03-2010 16:42:11

Hi Bob,


We will probably include a workaround also for this issue in the patch release coming next month.


Best regards,


Akos