Hydrocarbonylation of methyl acetate to ethylidene di:acetate - using catalyst contg. rhodium cpd. palladium cpd., ether-phosphane ligand and alkali(ne earth) iodide to give high selectivity

摘要

Prepn. of ethylidene diacetate (I) is by reaction of Me acetate with CO and H2 at 180-220 deg.C and 50-250 bar absolute using a catalyst consisting of (amts. based on Me acetate): (a) 0.05-0.50 mol% of a Rh cpd.; (b) 0.04-0.50 mol% of a Pd- or Ru-cpd.; (c) an ether-phosphane ligand in amt. such that the Rh/ligand mol ratio is 1:1-2; and (d) 3-15 mol% of an alkali(ne earth) iodide. The CO:H2 ratio is pref. 1-3:1. Added solvent is not necessary, but acetic acid can be added as solvent if required. ADVANTAGE - High conversions with high selectivity to (I) can be achieved using low catalyst concns.