Processes for the alcoholysis, inclusive of transesterification and/or disproportionation, of reactants are disclosed. The alcoholysis process may include feeding reactants and a trace amount of soluble organometallic compound to a reactor comprising a solid alcoholysis catalyst, wherein the soluble organometallic compound and the solid alcoholysis catalyst each independently comprise a Group II to Group VI element, which may be the same element in various embodiments. As an example, diphenyl carbonate may be continuously produced by performing transesterification over a solid catalyst followed by disproportionation, where a trace amount of soluble organometallic compound is fed to the transesterification reactor. Also disclosed is a process for reactivating a spent solid alcoholysis catalyst, such as a catalyst useful for transesterifications and/or disproportionations, the process including removing polymeric materials deposited on the catalyst and re-depositing catalytically active metals on the solid catalyst.