  Transition metal dichalcogenides exhibit rich phase diagrams dominated by the
interplay of superconductivity and charge density waves, which often result in
anomalies in the electric transport properties. Here, we employ the ionic
gating technique to realize a tunable, non-volatile organic ion intercalation
in bulk single crystals of molybdenum disulphide (MoS$_{2}$). We demonstrate
that this gate-driven organic ion intercalation induces a strong electron
doping in the system without changing the pristine $2H$ crystal symmetry and
triggers the emergence of a re-entrant insulator-to-metal transition. We show
that the gate-induced metallic state exhibits clear anomalies in the
temperature dependence of the resistivity with a natural explanation as
signatures of the development of a charge-density wave phase which was
previously observed in alkali-intercalated MoS$_{2}$. The relatively large
temperature at which the anomalies are observed ($\sim$$150$ K), combined with
the absence of any sign of doping-induced superconductivity down to $\sim$$3$
K, suggests that the two phases might be competing with each other to determine
the electronic ground state of electron-doped MoS$_2$.
