The acid-induced decomposition of o-methoxy, w-diazo, acetophenone might proceed by wither of two pathways. Huisgen (1) postulated that the mechanism was either “catalytic” (equation 1) or “stoichiometric,” (equation 2) and the differences in the mechanisms were directly related to acid concentration, nucleophilic power of the anion of the acid, and the ionic strength of the medium. Sheffer’s (2) reactions with o-methoxy, w-diazo acetophenone were carried out in ether, a non-polar medium. The aim of this researcher’s study was to determine the reaction course for the decomposition of o-methoxy, w-diazo acetophenone, in a highly polar, slightly nucleophilic medium containing nucleophilic acetate ion, to form either coumaranone or a straight chain product
