Several kinds of new reagents and methods for alkylation of organic compounds, particularly alcohols, have been developed by taking advantage of the π-electron deficient properties of 1,3,5-triazine. Based on the concept that 2,4,6-trialkoxy-1,3,5-triazine (TriAT) can be considered as the formal trimeric structure of the minimum units of an alkyl imidate, it was successfully demonstrated that TriATs act as acid-catalyzed O-alkylating reagents. N,N’-Dimethylated 6-(benzyloxy)-1,3,5-triazine-2,4(1H,3H)-dione (DMBOT) designed by alteration of the core structure of 2,4,6-tris(benzyloxy)-1,3,5-triazine (TriBOT) was found to show a superior reactivity in O-benzylation of alcohols; the reaction proceeds with a relatively mild pyridinium triflate as an acid catalyst. A trialkyltriazinylammonium salt, already activated by itself, spontaneously undergoes alkylation by dissolving it in an organic solvent including a nucleophile. Because all the compounds can be prepared from inexpensive cyanuric chloride within a few steps, they should be practically useful with respect to cost as well as their reactivities.