What is special about water as a solvent?
The bonds in water are POLAR. The result is that water has positive and negative ends, potentially capable of solvating discrete ions.
POLARITY is a result of charge separation. Because oxygen is more electronegative than hydrogen, it polarizes electron density towards itself such that oxygen acquires a partial negative charge, and the hydrogens each acquire a partial positive charge.
We can represent this bond polarity, this charge separation, by
In aqueous solution we would represent an ionic compound, say
In aggregate these ion-dipole interactions are strong enough to compensate for the breaking of the ion-ion interaction in solid sodium chloride. (In fact, the dissolution of sodium chloride in water is very slightly endothermic; the formation of new ion-dipole bonds is ALMOST enough to compensate for the breaking of the ion-ion interactions present in the solid.) Even a solvent such as ethanol (which does contain an hydroxyl group) is insufficiently polar to solvate discrete sodium and chloride ions.
By contrast organic solvents, such as hexanes or octanes or ethers (or oils) are incapable of solvating either positive or negative ions, because there is no similar degree of polarity for these solvents. There are no new bonds formed that can compensate for the breaking of ion-ion bonds; hence solubility of these ions in these media is untenable.