The invention describes a composition comprising a) an organic material which is susceptible to oxidative, thermal or light-induced degradation, and b) at least a compound of the formula (I) wherein Q is a direct bond (II), R1 is C1-C100alkyl, C2-C100alkenyl, C3-C12cycloalkyl or C3-C12cycloalkyl substituted by 1 to 5 C1-C4alkyl; R2 is a fluorine containing group, and R3 and R4 independently of each other are hydrogen or C1-C4alkyl. The compounds of the formula (I) are useful as reducers of surface energy for organic materials, for example, for increasing the oil and water repellency of organic materials.