Are There Dative Bonds In Isocyanides ?

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The discussion centers on the representation of HNC (hydrogen isocyanide) and isocyanides in chemical structures, specifically regarding the use of dative (coordinate) bonds versus triple bonds with charges. While some Indian publications advocate for the dative bond representation, this approach is not widely adopted in other resources like Wikipedia or Chem LibreTexts, which favor a triple bond depiction with formal charges. The dative bond representation is acknowledged as a possible structure but is noted to be uncommon and potentially confusing, especially since isocyanides are known to form dative bonds with metal centers. Additionally, the conversation touches on similar representations for other compounds, such as nitro groups, suggesting a trend in certain educational contexts to depict formal charges using dative bonds rather than the more conventional methods. Overall, the discussion highlights a divergence in chemical notation practices, particularly in Indian educational materials.
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Can We represent Isocyanides (RNC) with a dative bond ?
Okay guys, i had a question. Now in many indian publications and lecture rooms they say that we can represent HNC and isocyanides with a dative(coordinate) bond, but when i looked it up online, almost no one used such a structure. Wikipedia, Quora, Chem libre texts, etc, they describe it having a triple bond with charges.

Uh is the dative structure even correct ? Or is it an error that has been persistent is a bunch of indian publications ?Sources
With Dative Bond
1)Mtg-Interactive Irganic Chemistry by Girijesh Dubey (pg 623)
2)Resonance KVPY-SX Stream : Chemistry
1571210566226716413443.jpg
 
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The structure can be represented as a resonance hybrid, as on the Wikipedia page:
1571222499839.png

The double-bonded form has a lone pair on nitrogen and an empty orbital on carbon (1 lone pair rather than 2). N can use its lone pair to bond with the empty C orbital to make a triple bond, then N has a formal positive charge and C a formal negative charge. (You can draw the third bond as dative with an arrow, but that is not usual.)
The triple-bonded structure can be considered as related conceptually to the cyanide by removing a proton (and a neutron, but we don't worry about that) from the N atom of the cyanide and adding it to the C atom. This produces an isoelectronic molecule, but with charges as shown. The charges are not always drawn, especially when we are not focussing on the bonding but just representing the compound (e.g. saying A reacts with B to give C).
 
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Ah, okay . So we can use a dative bond, but it aint a common format right ?

Also thank you for explaing the structure of the molecule, i have a tendency of getting confused with the nitrogen lone pair while solving reaction based questions, this helped clear some doubts about it
 
I admit, I've never seen an isocyanide drawn that way. It seems like a recipe for confusion, especially because isocyanides themselves are really good at forming dative bonds with metal centers (as @mjc123 's vinyl carbene resonance structure suggests).
 
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TeethWhitener said:
I admit, I've never seen an isocyanide drawn that way. It seems like a recipe for confusion, especially because isocyanides themselves are really good at forming dative bonds with metal centers (as @mjc123 's vinyl carbene resonance structure suggests).
Oh and that's not all

We represent the Nitro group(-NO2) the same way too, istead of showing charges, we show one dative bond with one oxygen and a double bond for the other

There were some other compounds too, i can't recollect though. Basically all those compunds with formal charges were represented with dative bonds. I guess its an Indian thingie
 
It seems to be a general thing, e.g. ammonia-boron trifluoride may be drawn as
H3N→BF3
or H3N+-B-F3
 
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