| 摘要 |
<p>Process to prepare a 5-cyanovaleric acid or its ester by carbonylation of a pentenenitrile, wherein pentenenitrile is reacted with carbon monoxide and water or an alcohol in the presence of a catalyst system. The catalyst system comprises: (a) a metal of Group VIII or a compound thereof and (b) a bidentate phosphine, arsine and/or stibine ligand, wherein the bidentate ligand has the general formula (I): R?1R2-M1-R-M2-R3R4¿ wherein M?1 and M2¿ are independently P, As or Sb, R is a divalent organic bridging group, which bridging group. (c) an acid having a pKa less than 3, as measured at 18 °C in an aqueous solution.</p> |
