Oxidative carbonylation is an alternative to phosgenation. The advantage is the avoidance of phosgene.  Using copper catalysts, dimethylcarbonate is prepared in this way:
: 2 MeOH + CO  +  1/2 O → MeOC(O)OMe + HO
Diphenyl carbonate is also prepared similarly, but using palladium catalysts.  The Pd-catalyzed process requires a cocatalyst to reconvert the Pd(0) to Pd(II).  Manganese(III) acetylacetonate has been used commercially.