A catalyst suitable for use in reactions catalyzed by strong base is provided. The catalyst comprises an organic compound containing a Group VA element for example an amine or phosphine supported on a solid which is insoluble in the reaction mixture. The catalyst may be activated by treatment with an epoxide. Catalysts in which the amine is an amidine or a guanidine are particularly effective.
The present invention provides a process for preparing urethanes and carbonates from an amine or an alcohol, carbon dioxide and a hydrocarbyl halide. The amine or alcohol is reacted with carbon dioxide in a suitable solvent system and in the presence of an amidine or guanidine base, to form the ammonium carbamate or carbonate salt which is then reacted in a polar aprotic solvent with a hydrocarbyl halide. Polymer products can also be prepared utilizing this process or utilizing the resulting urethanes and carbonates under standard polymerization conditions.