Processes and systems for producing olefin epoxides with three or more carbon atoms by oxidation of the corresponding branched hydrocarbons using oxygen are disclosed. An example process for producing olefin epoxides may include oxidizing a branched alkane to produce at least an organic hydroperoxide. The example process may further include epoxidizing a branched alkene by a catalytic reaction with least a portion of the organic hydroperoxide to produce at least an olefin epoxide and an alcohol. The example process may further include converting at least a portion of the alcohol to either additional branched alkane and/or additional branched alkene.