The importance of selectively oxidizing aniline into value-added chemicals azoxybenzene and nitrobenzene is well-recognized in organic synthesis. However, the lack of control over selectivity and the complex synthesis of costly catalysts significantly hinder these reactions' industrial applications. In this work, an environmentally friendly approach was developed for the selective oxidization of substituted anilines. This method involves adjusting the strength of alkalinity with peroxide as the oxidant, without the addition of any metals or additives. A mild base (NaF) facilitated azoxybenzene formation, while a stronger base (NaOMe) enabled the synthesis of nitroaromatics. These protocols are user-friendly and scalable, accommodating various substitution patterns and functional groups, yielding products with high to excellent yields. The findings of this work present a framework for investigating base catalysis in organic synthesis and provide a viable and effective approach for selectively oxidizing aniline.