This dissertation summarizes the employment of simple, inexpensive, and easily accessible manganese and iron catalysts for the oxidative valorization of unactivated alkenes to epoxides and alkanes to ketones/alcohols. In a first project, tert-butyl hydroperoxide was used as terminal oxidant and quinoline was shown to be the crucial additive for manganese-catalyzed epoxidation of unactivated alkenes. In a consecutive project, the efficiency of this transformation was raised by developing an improved manganese catalyst using the more benign oxidant hydrogen peroxide. In this case, the employment of N-heterocycles also proved to be crucial for achieving high yields of epoxides. This system was additionally capable of selectively oxidizing alkanes to ketones, as well as secondary alcohols to ketones. In a last project, an iron catalyst was used to transform unactivated alkanes into corresponding mixtures of ketones and alcohols, using hydrogen peroxide as terminal oxidant.