Oxidative Carbonylation of Alcohols to Carbonates, Oxalates, and Carbamates

Oxidative Carbonylation of Alcohols to Carbonates, Oxalates, and Carbamates 

Oxidative carbonylation of alcohols in the presence of CO provides an economically viable route to dialkyl carbonates and/or oxalates (Eqs. (8.4) and (8.5)), both of which have important industrial applications. Dialkyl carbonates (e.g., dimethyl carbonate, propylene carbonate) are excellent solvents for a variety of organic substances [14]. Dialkyl oxalates have utility as solvents, C2 building blocks in fine chemicals synthesis, and intermediates in the manufacture of oxamide (as a fertilizer) [15]. Hydrogenation of dialkyl oxalates provides an alternative route to ethylene glycol that is independent of oil-derived resources [15,16]. 

A major challenge in Pd-catalyzed oxidative carbonylation reactions is the decomposition of catalysts into inactive metallic Pd, promoted by the strong reducing CO reagent. Successful examples of Pd-catalyzed oxidative carbonylation typically 

Ube has also developed Pd/MeONO-based gas-phase processes for the production of dimethyl oxalate and dimethyl carbonate (Eqs. (8.9) and (8.10)) using 

Catalyst A PdCl2, FeCIs (Bayer) Catalyst B Pd/C, Kl (Asahi Chemical) 

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