Methyltrioxorhenium(VII) is used as a catalyst for various transformations such as olefin metathesis. It is associated with hydrogen peroxide and used as an oxidizing agent. It is used to prepare acid or ester from the corresponding terminalalkynes. It is a catalytic oxidant used with urea hydrogen peroxide to prepare nitrones. It reacts with 2-methylnaphthalene to get 2-methyl-1,4-naphthoquinone (Vitamin K3). Further, it catalyzes the reaction with aldehydes and diazoketones to get an alkene. In addition to this, it is used as an effective antioxidant under various conditions.