摘要 |
<p>Hydroxyaromatic compounds such as phenol are carbonylated with oxxygen and carbon monoxide in the presence of a catalyst system comprising a Group VIIIB metal, preferably palladium; at least one bromide or chloride salt, preferably sodium bromide or a tetraalkylammonium bromide; at least one organic bisphosphine such as 1,3-bis(diphenylphosphino)propane or 1,4-bis(diphenylphosphino)butane; and a compound of a metal other than a Group VIII metal having an atomic number of at least 44, preferably a lead bromophenoxide. There may also be present a polar organic liquid as a cosolvent.</p> |