Unraveling the role solvent plays chemical reactions – the case of Frustrated Lewis Pairs
Title: Unraveling the role solvent plays chemical reactions – the case of Frustrated Lewis Pairs
DNr: SNIC 2015/1-208
Project Type: SNIC Medium Compute
Principal Investigator: Timofei Privalov <priti@organ.su.se>
Affiliation: Stockholms universitet
Duration: 2015-05-29 – 2016-06-01
Classification: 10407 10404 10405
Keywords:

Abstract

As a continuation of our work on the mechanisms of the Frustrated Lewis Pair reactions, at this stage the question we plan to address is the role of solvent (solute-solvent interactions) on the mechanism of reactions involving frustrated Lewis pairs (FLPs) – e.g., stoichiometric mixture of a Lewis acid and a Lewis base unquenched for steric reasons. Frustrated Lewis pairs (FLPs) represent a new class of reactivity and usefulness of bond-activation with FLPs is already well recognized. The role solvents play in the structure of solutes and mechanisms of chemical reactions has long been of general interest throughout chemistry. To begin with, we will investigate whether solvent can open up a two-step FLP reaction path – one that complements the path described by de facto standard transition-state calculations. Results of our prior work indicate that this could indeed be possible. An idea is that P-C and O-B bonds – two new bonds observed in the formate-type product of the reaction between the phosphorous/boron FLP and the dissolved carbon dioxide gas – could be formed disconcertedly because environment (solvent) could stabilize the association between phosphorous Lewis base and carbon dioxide in polar organic solvents. This idea will be tested using the first principles (Born-Oppenheimer) molecular dynamics with explicit solvent at room temperature. With calculations of the infra-red absorption spectra and other experimental observables, we plan to prepare a foundation for the experimental corroboration of our results. After the initial stage described above and using in full the methodology described in the Resource Usage section, we plan to expand our work to studies of the mechanisms of N2O, CO, NO and SO2 capture by FLPs at room temperature, [1], with the focus on (i) the role of solute-solvent interactions, (ii) the dissociation pathways of LB-X-LA adducts at elevated temperature, and (iii) structural and electronic properties of dative bonds in adducts with N2O, CO, NO and SO2. Results of the previous project are published: (a) Pu, M., Privalov, T., ChemPhysChem, 2014, 15, 3714; (b) Pu, M., Privalov, T., ChemPhysChem, 2014, 15, 2936; also, see our recet review for details [Pu, M., Privalov, T., “Chemistry of intermolecular frustrated Lewis pairs in motion: emerging perspectives and prospects”, Isr. J. Chem., 2015, 55, 179].