Has a carbon compound ever been found having an ionic bond?

Question

Though it is highly unlikely, has any carbon compound been found to make an ionic bond and to exhibit ionic properties?

Answer 1

I'd need you to be somewhat more specific about this question. If you are just asking about a carbon containing compound, then yes. Carbonate.

Answer 2

If you look up the Pauling electronegativity scale for each element, carbon is right in the middle with a value of about 2.6: https://www.angelo.edu/faculty/kboudrea/periodic/trends_electronegativity.htm

To form an ionic bond with carbon, you'd need an electronegativity difference of 2.0. You would need an element with an electronegativity of 0.6 or less, or an element with an electronegativity of 4.6 or greater. Alas, these elements do not exist. The lowest electronegativity is for Francium (unstable and impractical to work with anyway), at 0.70. The highest electronegativity is for Fluorine, at 4.0. These don't quite make a fully ionic bond with carbon.

Of course these bonds really do fall onto a continuum: there is definitely some 'ionic character' to a Lithium-Carbon bond in a substance such as LiCH₃, methyllithium, in fact this substance often reacts as if it contains a CH₃^- ion, but it's not a fully ionic bond. Carbon just doesn't do those, because it sits right in the middle of the electronegativity scale!