Allylic alcohol epoxidation and dehydrogenation reactivity is distinguished when VO(acac)2 is used in solution or anchored in a metal-organic framework (MOF). The chemical mechanism depends on the electronic profile of alkene substituents when the vanadyl complex is used in the homogenous phase. However, confinement effects imparted by MOF channels allow gaining control of the chemoselectivity toward the dehydrogenation product.