| 摘要 |
<p>The solubility and stability of rhodium catalysts in rhodium-catalysed carbonylation of alkyl esters or alkyl ethers under substantially anhydrous conditions to produce carboxylic acid anhydrides is improved by the use of co-promoters selected from the group: 1,3-dialkyl-4-methylimidazolium iodide; 1,3-dialkyl-4-ethylimidazolium iodide; 1,3-dialkyl-4-n-propylimidazolium iodide; 1,3-dialkyl-4-isopropylimidazolium iodide; 1,3-dialkyl-4-n-butylimidazolium iodide 1,3-dialkyl-4-sec-butylimidazolium iodide 1,3-dialkyl-4-tert-butylimidazolium iodide; 1,3-dialkyl-2,4,5-trimethylimidazolium iodide and mixtures thereof where the alkyl groups are independently C1 to C20 alkyl.</p> |
