We present a Molecular Dynamics (MD) study of a model for AH-B A - -H + B reactions in liquid chloromethane. The parameters of the model are fitted to those of typical OH-N proton-transfer complexes. We outline the influence of the properties of the complex on the proton transfer mechanism. We discuss also the static and dynamical role of the solvent, the tunneling contribution to the rate, and the associated kinetic isotope effect. The rate calculations are based on a quantum path-integral method, focused on the static properties of the centroid of the proton thermal path. The results are compared to those of different approaches, including a curve-crossing semiclassical formalism and a classical theory corrected by zero-point-energy and tunneling factors. The latter is shown to be unable to describe the quantum effects properly in the present case.