C–Hortho⋯Pd interactions in palladium complexes derived from tetrasulfur-difluorinated ligands. Experimental, computational and catalytic studies

• Published in: Polyhedron 2019-11, Vol.173, Article 114115
• Main Authors: González-Montiel, Simplicio, Sandoval-Chávez, César Ignacio, Muñoz-Granados, Oscar, Martínez-Otero, Diego, Vásquez-Pérez, J. Manuel, Cruz-Borbolla, Julián, Velázquez-Jiménez, René, López, Jorge A.
• Format: Article
• Language: English
• Subjects: Catalysis; Cross-coupling reactions; C–H⋯Pd interactions; Palladium complexes; Theoretical calculations
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2019.114115

Two Pd(II) complexes were obtained employing tetrasulfur-difluorinated ligands. Their molecular structures were determinated in solid state which suggested the possible existence of anagostic Pd⋯Hortho interactions those interactions were also identified by NCI analysis. The catalytic activity of these complexes was evaluated in Suzuki-Miyaura cross-coupling reaction. [Display omitted] The symmetric ligands [Ar-S-CH2-Ph-S-(CH2)-]2, L1 (Ar = o-FPh) and L2 (Ar = p-FPh), and their PdII complexes (1 and 2) were synthesized and structurally characterized. Molecular structures of complexes 1 and 2 display the L1 and L2 ligands coordinating palladium in a κ2-SS bidentate fashion. The metal center exhibits a square planar geometry involving the two sulfur atoms and two chloride atoms which are oriented in cis disposition. Interestingly, the two ortho-hydrogen atoms from the phenyl rings in both complexes are engaged in Pd⋯Hortho interactions with distances from 2.976 to 3.280 Å. These distances can suffer an increase or decrease in their longitude due to the presence of intramolecular C–H⋯π interactions. Additionally, the presence of Pd⋯H interactions in palladium complexes (1 and 2) were identified by an NCI analysis. The complexes 1, 2 and a similar complex 3 that also displays Pd⋯Hortho interactions have been evaluated in the Suzuki-Miyaura cross-coupling reactions.