The present invention relates to a method for producing an organometallic catalyst and an organometallic catalyst when produced by the method. The method comprises the steps of combining a polycarboxylic acid or anhydride and a metal-oxide, metal-hydroxide or metal-salt with a solvent at a temperature and pressure at which the solvent exists as a supercritical or near-critical fluid. The polycarboxylic acid or anhydride is reacted with the metal-oxide, metal-hydroxide or metal-salt for sufficient time and under sufficient temperature and pressure to produce the organometallic catalyst. The present invention also relates to a process for making a poly(alkylene carbonate) in the presence of a catalytic amount of the organometallic catalyst produced by the method.