A mild base-promoted three-component deconstructive functionalization reaction of cyclic 1,3-diketones with aryl diazonium tetrafluoroborates in the presence of alcohols is reported, enabling direct ring-opening of unstrained cyclic ring systems to produce three types of skeletally diverse 1,n-ketoesters, namely, linear 1,5- and 1,4-ketoesters and ortho-ketobenzoates, with moderate to good yields. The methodology has the potential to be widely used throughout organic synthesis due to the use of easily accessible substrates, such as cyclic 1,3-diketones and aryl diazonium tetrafluoroborates, with different substitution patterns and mild reaction conditions. To create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed. Display omitted