Modeling of protodeborylation of tris(pentafluorophenyl)borane (BCF) under conditions relevant to epoxide ring-opening reactions

In this work, we develop a microkinetic model for the protodeborylation of tris(pentafluorophenyl)borane (BCF) under reaction conditions relevant to epoxide ring opening by 1-propanol. The model builds on density functional theory calculations that capture shells of explicit molecules near the boron center that participate in hydrogen bonding interactions. Decomposition of BCF occurs via both hydrolysis and alcoholysis, and participation of the decomposition product, bis(pentafluorophenyl)borinic acid, as a catalyst is also considered. Given all of the possible multi-body species, 26 distinct reaction pathways are included in the model. The model results are compared with experimental data that was collected as a function of reaction temperature, water content, and 1-propanol concentration. Speciation and net flux analysis based on the model results reveal the interplay between species binding and facile elementary steps for decomposition and rationalize the seemingly counterintuitive result that rates of protodeborylation are lower in 1-propanol than in non-protic solvents like xylenes. Furthermore, this model shows robustness when benchmarked against experimental trials across a broad range of conditions that were not used for training. This work aims to offer a foundation for predicting borane catalyst degradation pathways and designing more robust catalytic systems for sustainable chemical processes such as epoxide ring-opening reactions.