A method for preparing pyrimidin-2-ylacetic acid esters of the general formula: ##STR1## wherein R is C.sub.1-6 -alkyl, C.sub.3-6 -cycloalkyl, aryl or arylalkyl and R.sup.1 to R.sup.3, independently of one another, are hydrogen, C.sub.1-6 -alkyl, fluorinated C.sub.1-6 -alkyl, C.sub.1-6 -alkoxy, (C.sub.1-6 -alkoxy)-C.sub.1-6 -alkyl or (C.sub.1-6 -alkoxy)carbonyl. These esters are obtained from the corresponding 2-(halomethyl)-pyrimidine, the corresponding alcohol ROH and carbon monoxide in the presence of a palladium-phosphine complex and a base. Pyrimidin-2-ylacetic acid esters are intermediates in the preparation of herbicides.