Noriaki Manada

A Novel Synthesis of Alkyl Chloroformate in the Gas Phase by a Palladium-Catalyzed Reaction Using Cl2, CO, and Alkyl Nitrite

A novel synthesis of chloroformate was developed by a palladium-catalyzed reaction of Cl2, CO, and alkyl nitrite in the gas phase. When PdCl2/γ-Al2O3 or PdCl2/SiO2 was employed as a catalyst, chloroformate was formed in good yield and with high selectivity. It was confirmed that the reaction did not proceed via phosgene. Cl2 is directly converted to methyl chloroformate. No HCl was formed. The reaction temperature greatly influenced the formation rate of chloroformate, and its selectivity depended on the nitrite/Cl molar ratio very drastically. The dependence of the formation rate on the concentrations of CO and methyl nitrite was also examined.