The intracluster elimination reactions in solvated alkaline earth metal monocation clusters, M+Ln, are known to be size-dependent, indicating links between chemical reactivity and the solvation environment controlled by the cluster size. For the methanol and ammonia clusters, there are a number of competing elimination channels involving the breaking of O-H, C-H, O-CH3, or N-H bond. In this report, we focus on the four clusters with only one solvent molecule and systematically map out the reaction paths and intermediates. The interaction between the metal ion and the departing H atom or CH3 group varies considerably, depending on the interaction between the metal ion and the remaining group. The understanding of the nature of these interactions and the evaluation of various theoretical levels in treating these reactions provide a solid base for the investigation of the solvation effects on the chemical reactivity of the larger clusters.