Are There Dative Bonds In Isocyanides ?

[Navin]

TL;DR

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

 

[mjc123]

The structure can be represented as a resonance hybrid, as on the Wikipedia page:

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).

 

[Navin]

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

 

[TeethWhitener]

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).

 

[Navin]

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

 

[mjc123]

It seems to be a general thing, e.g. ammonia-boron trifluoride may be drawn as
H₃N→BF₃
or H₃N⁺-B^-F₃