Theoretical investigation of hydrogen abstraction from Fluorinated propanones and Fluorinated propanals

Per- and polyfluoroalkyl substances (PFAS) are a class of thousands of industrially used compounds often called “forever” chemicals because of their slow degradation process that leads to accumulation in soil, dust, drinking water, and the body. PFAS are used for their grease and water resistance properties but some of these compounds are toxic at extremely low levels. To better understand the effects of these types of compounds, the main pathways of their degradation need to be further investigated. This study analyzes computationally the hydrogen abstraction reactions by both hydroxyl radical and triplet oxygen atom for all possible fluorinated propanones and fluorinated propanals. Hybrid density functional theory calculations (mPWB1K functional in conjunction with 6-31+G(d,p) basis set) were used to determine the location of the saddle points as well as energetic parameters for all possible reaction pathways to ultimately gain a better understanding of the reactivity of these molecules. Most likely reaction pathways were predicted, and comparisons were made among all fluorinated propanones and fluorinated propanals. The effects of the hydroxyl hydrogen, carbonyl group, and number and position of fluorine atoms on the saddle points were analyzed.