b respectively suitable acids for use in the practice of the method of the present invention include inorganic acids such as hydrochloric acid hydrobromic acid sulfuric acid phosphoric acid and boric acid and water miscible organic acids such as formic acid acetic acid propionic acid oxalic acid malonic acid and tartaric acid the acid should be used in at least an amount capable of protonating all of the liberated dimethylamine thereby maintaining an at least moderately acidic environment for ring closure of imine intermediate 3 and completion of the zaleplon forming reaction an acid may be added individually as such to the reaction mixture alternatively the acid may be added as the proton donating component of an acid addition salt of ethylacetamide 1 or pyrazole 2 thus it will be appreciated by those skilled in the art that up to about two equivalents of acid may be added by using acid addition salts of the starting materials therefore separate individual addition of an acid as such is not strictly necessary to establish acidic conditions preferred acids include hydrochloric acid and phosphoric acid either of which is preferably present in the reaction mixture in an amount of from about one to about two molar equivalents with respect to the limiting reagent starting materials 1 and 2 may be used in any ratio the one present in the lesser molar amount constitutes the limiting reagent to.