The Synthesis Of Diethyl Malonate By Palladium-catalyzed Carbonylation Of Dichloromethane

In recent years, carbonylation method is an increasingly hot spot of current chemicalresearch for its high atom economy and easily available CO sources. And transition-metalcatalyzed carbonylation method can be used for the synthesis of a variety of aldehydes,ketones, esters and other carbonyl compounds. Among these, diethyl malonate (DEM) isan important chemical raw material and organic synthesis reagents, which is widely usedin drugs, dyes, perfumes, and other fields. Diethyl malonate is traditionally produced bysodium cyanide. However, this method is complex and has a low yield, especially highlytoxic sodium cyanide can lead to environmental pollution.We present a direct and highly efficient approach for synthesizing diethyl malonate bythe carbonylation of methylene chloride. This reaction process, which is simple, short andmild, can be regarded as an efficient green method. Different catalytic properties ofdifferent catalyst systems in carbonylation of dichloromethane were explored. Many effectfactors such as ligand, solvent, base, and reaction pressure were investigated.Contents presented in this paper were summarized as follows:Firstly, the standard molar enthalpy change, standard molar entropy change andstandard molar Gibbs function of the reaction were estimated according to the functionalgroup contribution method. The results show that the reaction can easily performed todiethyl malonate, elevated temperature does not facilitate the creation of the product.Secondly, explored catalytic properties of different catalysts in the carbonylation ofdichloromethane.Thirdly, investigated many effect factors such as promoter, solvent, base, reactionpressure and material ratio.Finally, the mechanism of carbonylation of dichloromethane to diethyl malonate wasdiscussed.