| 摘要 |
PURPOSE:To prepare the titled compound, in a sophisticated manner, by the carbonylation reaction of dimethyl acetal with CO in the presence of a specific metallic catalyst and a halogenated cocatalyst, under essentially anhydrous conditions. CONSTITUTION:The titled compound is prepared by reacting dimethyl acetal of formula I with CO in the presence of a catalyst comprising one or more VIII group metals and a cocatalyst comprising an iodide or a bromide. Pd, Rh and Ni are effective as the metallic catalyst, and the cocatalyst is pref. an iodide. Furthermore, the presence of an organic accelerator (e.g. monomethylamine, dimethylamine, etc.) is preferable. The use of a solvent such as acetic acid, methyl acetate, etc. stabilizes the catalyst and the reaction system, and increases the selectivity and the yield of the titled compound. In that case, the water content of the reaction system is pref. <=3mol%. |
