2015 Paul N. Rylander Award Address: Selected Advances in Catalysis and Reactor Systems for the Generation of Acetates and Propionates Using Carbonylation

The introduction of carbonyl functionality using carbonylation in its various forms represents some of the largest volume and most successful applications of homogeneous catalysis in the chemical industry. These reactions have a diversity of mechanisms which, once understood, allow the manipulation of the catalytic processes in unique ways and offers options for interesting reactor designs. This review will focus on the generation of acetates and propionates, two of the simplest entities that can be generated by carbonylation, and discuss how mechanistic knowledge can be used to develop new catalysts and new reactor configurations in carbonylation processes when desired. Examples will include the development of (i) a Rh–MeI–Li catalyzed carbonylation of methyl acetate to acetic anhydride, (ii) a Mo catalyzed carbonylation of ethylene to propionic acid and propionic anhydride, (iii) a molecular Ir–La catalyst supported on carbon for heterogeneous carbonylation of methanol, (iv) alternative reactor designs including a fluidized bed reactor for heterogeneous carbonylations, and (v) a vapor takeoff reactor using ionic liquids for the generation of acetates and propionates which ultimately led to a process for the generation of acetic acid that uses N-methylpyridinium iodide salts to replace methyl iodide as a cocatalyst in Rh catalyzed methanol carbonylation.