Co-crystals of NHC Au(I) Aryl Complexes with Iodoperfluoroarenes as a Platform for the Study of Au(I) Involving Halogen Bonding

Abstract

Among the known types of non-covalent interactions with Au(I) metal center, Au(I) involving halogen bonding (XB) remains a rare phenomenon that has not been studied systematically. Herein, using five N-heterocyclic carbene (NHC) Au(I) aryl complexes and two iodoperfluoroarenes as XB donors, we demonstrated that the XB involving the Au(I) metal center can be predictably obtained for neutral Au(I) complexes using the example of nine co-crystals. The presence of XBs involving the Au(I) center was experimentally investigated by single-crystal X-ray diffraction and solid-state 13C CP-MAS NMR methods, and their nature was elucidated through DFT calculations, followed by electron density, electrostatic potential, and orbital analyses. The obtained results revealed the connection between the structure of Au(I) complexes as XB acceptors and the geometrical, electronic, and spectroscopic features of XB interactions, as well as the supramolecular structure of the co-crystals