Theoretical Investigation on Selenium-Based Frustrated Lewis Pairs

The Frustrated Lewis Pairs (FLP) concept recently demonstrated to be a powerful way to activate small molecules and promote a plethora of organic reactions without the help of transition metals. This strategy is based on simple combinations of Lewis acids and bases that are sterically or electronically hindered from forming classical Lewis acid-base adducts. Generally, the Lewis acid is a fluorinated compound of boron or aluminum, and the Lewis base is based in most cases on phosphorous, nitrogen or, seldom, oxygen. To the best of our knowledge, no attempt has been made to isolate, characterize and test in catalysis selenium-based FLP. In the present contribution, the interaction between sterically encumbered organoselenium compounds, as selenides and selones, and standard Lewis acids, as B(C6F5)3 and less-fluorinated boranes, will be studied by DFT calculations and compared to the interaction present in already known P-based FLPs. Attempts will be made to find bench-stable FLPs, with the aim to simplify the experimental studies and encourage the possible applications to real systems. Energy Decomposition Analysis results are shown and discussed, showing that selenium-based FLPs are theoretically possible. For the most promising candidates, the products of the activation of small molecules (H2 or CO2) will be theoretically optimized, in order to check if the reaction would be thermodynamically favored.