The ammonium skeleton, which has cationic charge on the nitrogen atom, is include in many important molecules such as bioactive molecules, surfactants, and organocatalysts due to its unique physical properties. However, at present, there are only a limited number of methods for synthesizing ammonium compounds, and the chemical space of the ammonium skeleton has not been fully exploited. In our laboratory, we will solve this problem by establishing editing methods of ammonium skeletons and pursue new science pioneered by ammonium molecules.