Can an organic compound have an ionic bond?
There's a large number of salts with organic anions (e.g. potassium hydrogen tartrate) or organic cations (e.g. tetrabutylammonium hexafluorophosphate)

There are even salts, in which both the anion and the cation are organic compounds with covalent bonds. This is often used in pharmaceuticals. Here the active component appears in protonated form and is served as a salt with the conjugated bases of carboxyclic acids (e.g. citrates, succinates, etc.)