新型YS类高分子铑配合物催化甲醇羰基化反应制备乙酸和乙酐

Carbonylation of Methanol to Acetic Acid and Acetic Anhydride Catalyzed by Copolymer Rhodium Complexs

以含有两种不同配位原子的线型或交联大孔球型共聚物为配体的新型铑配合物,能在温和条件下催化甲醇羰基化为乙酸和乙酐.实验结果表明,这些新型共聚物铑配合物具有鳌合型顺-二羰基铑(Ⅰ)的结构特征,并有良好的热稳定性及高的催化活性和选择性.

A series of heterogenized rhodium complex catalysts for the carbnylation of methanol have been synthesized by the reaction of tetracarbonyldichloro-dirhodium with linear and cross-linked copolymers. These complexes were high catalytic in carbonylation of methanol to acetic acid and acetic anhydride. The active centers of these catalysts consist of (a) a cis-di-carbonyl rhodium moiety coordinated with the borderline base pyridine N and adjacent oxygen to form N→Rh and O→Rh coordination bond, respectively, and (b) the said moiety coordinated with two adjacent pyridine N's to form two N→Rh bonds. The former plays a more active role than the latter in catalysts. These catalysts are thermally stable. With methyl iodide as promoter, methanol in acetic acid could be carbonylated to acetic acid and acetic anhydrine simultaneously as final products with a turnover rate at 10~4 moles methanol converted/(mol Rh·h^(-1)).