Factors Governing the Catalytic Insertion of CO2 into Arenes - A DFT Case Study for Pd and Pt Phosphane Sulfonamido Complexes

Markus Hölscher; Gregor Kemper; Sangeth Jenthra; Carsten Bolm; Walter Leitner

doi:10.1002/chem.202104375

Factors Governing the Catalytic Insertion of CO₂ into Arenes - A DFT Case Study for Pd and Pt Phosphane Sulfonamido Complexes

Chemistry. 2022 Apr 22;28(23):e202104375. doi: 10.1002/chem.202104375. Epub 2022 Mar 21.

Authors

Markus Hölscher¹, Gregor Kemper¹, Sangeth Jenthra¹, Carsten Bolm², Walter Leitner^{1

3}

Affiliations

¹ Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringer Weg 2, 52074, Aachen, Germany.
² Institut für Organische Chemie, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
³ Max-Planck-Institut für Chemische Energiekonversion, Stiftstraße 34-36, 45470, Mülheim a. d. Ruhr, Germany.

Abstract

The potential of Pd/Pt complexes for catalytic carboxylation of arenes with CO₂ is investigated by means of computational chemistry. Recently we reported that the bis[(2-methoxyphenyl)phosphino]-benzenesulfonamido palladium complex 1 inserts CO₂ reversibly in its Pd-C(aryl) bond generating carboxylato complex 2. In the present work we study how geometric and electronic factors of various ligands and substrates influence the overall activation barrier (energy span, ES) of a potential catalytic cycle for arene carboxylation comprising this elementary step. The tendency of the key intermediates to dimerize and thus deactivating the potential catalysts is examined as well as the role of the base, which inevitably is needed to stabilize the reaction product. We show that Pd and Pt complexes I(Pd)-L16-S1 and I(Pt)-L16-S1 do not dimerize, enable the computation of complete catalytic cycles, and show interestingly low ES values of 26.8 and 24.5 kcal/mol, respectively.

Keywords: CO2; Catalysis; DFT; Palladium; Platinum; aromatic acids.