The invention relates to a method for producing -ketoenol esters of the
general formula (Ia) or (Ib), wherein Ar, Ra and Rb are defined
as in claim 1. The inventive method is characterized by reacting an arylhalogenide
of the general formula (II) with a 1,3-diketone of the general formula (III) or
the tautomers thereof in a carbon monoxide atmosphere in the presence of an alkali
and a catalyst that contains at least one transition metal of group VIII of the
periodic system
##STR1##
