Direct conversion of dimethyl ether and CO to acetone via coupling carbonylation and ketonization

Acetone is currently produced by large amount of propylene and benzene, and its synthesis from a cheap and non-petroleum material has not yet been reported. Here, we present a new method for acetone production, which involves the carbonylation of dimethyl ether (DME) to methyl acetate and its subsequent ketonization to acetone over pyridine-modified H-mordenite. This convenient approach offers an acetone selectivity of 73% (CO2 excluded) and a DME conversion of 100% at 553 K. Spectral and isotopic studies revealed that the ketonization of methyl acetate was promoted by carbonylation, while the formation of a ketene intermediate was demonstrated by the formation of CH2DCOOD and two types of pyrones. A ketene-based ketonization mechanism was also proposed based on the kinetic isotope effect of CH2=13C O, indicating that the acetyl moiety contributed to the acyl part of acetone, while the ketene moiety was responsible for the alkyl part of acetone and the generation of CO2.