This disclosure provides a process for making transition metal carboxylate compositions by combining in an polar aprotic first solvent a transition metal precursor and a Group 1 or Group 2 metal carboxylate under substantially acid-free and substantially anhydrous conditions, to generate a mixture comprising the transition metal carboxylate composition. Optionally, the transition metal carboxylate composition can be purified, for example, by substantially removing the first solvent provide a residue comprising the transition metal carboxylate composition, and also optionally, further by extracting the transition metal carboxylate composition from the residue with a non-coordinating second solvent to provide an extract comprising the transition metal carboxylate composition.