Soluble Two‐Dimensional Covalent Organometallic Polymers by (Arene)Ruthenium‐Sulfur Chemistry

Abstract

International audienceA class of two-dimensional (2D) covalent organometallic polymers, with nanometer-scale crosslink- ing, is obtained by arene(ruthenium) sulfur chemistry. Their ambivalent nature, with positively charged crosslinks and lypophylic branches, is the key to the often sought-for and usually hard- to-achieve solubility of 2D polymers in various kinds of solvents. Solubility is here controlled by the planarity of the polymer, which in turn controls Coulomb interactions between the polymer layers. High planarity is achieved for high symmetry crosslinks and short, rigid branches. Owing to their solubility, the polymers are straightforwardly processable, and can be handled as powders, deposited on surfaces by mere spin-coating, or suspended across membranes by drop-casting. The novel 2D materials are potential candidates as flexible membranes for catalysis, cancer therapy, and electronics

Nano-sheets of two-dimensional polymers with dinuclear (arene)ruthenium nodes, synthesised at a liquid/liquid interface

“…In the green-shaded area, the precursor exhibits a characteristic low-energy band at 1679 cm -1 , typically assigned to a C=O stretching mode. 16,21,22 As expected, this band is absent for [Ru 2 (C 6 Me 6 ) 2 (p-S-C 6 H 4 -C 6 H 4 -CH=N-C 6 H 4 -CN) 3 ]Cl. Instead, a band at 1696 cm -1 , characteristic of a C=N stretching mode, 16,21,22 is observed.…”

“…As expected, for [Ru 2 (C 6 Me 6 ) 2 (p-S-C 6 H 4 -C 6 H 4 -CH=N-C 6 H 4 -CN) 3 ]Cl, this band is absent. Instead, a band at 1696 cm −1 , characteristic of a C=N stretching mode [16,21,22], is observed. Neither the C=O nor the C=N stretching modes show up in the wavenumber range in the nano-sheet spectra.…”

“…In the green-shaded area, the precursor exhibits a characteristic low-energy band at 1679 cm -1 , typically assigned to a C=O stretching mode. 16,21,22 and the polymeric nano-sheet suspended across the Si3N4 grid, taken with a laser wavelength of 532 nm laser. The power density was 1.7 mW/mm 2 and 0.17 mW/mm 2 for the powders and polymer respectively.…”

“…These units are based on a closed trigonal bipyramid Ru 2 S 3 framework which are surrounded by two arene ligands [15]. Such ligands can be designed to promote the solubility of the final molecular complex, and even of 2D polymers by decreasing electrostatic interactions between molecules or polymeric nanosheets [16]. Using the reaction between -SH and di-μ-chlorobis[(arene)chlororuthenium(II)], many types of functional group can be introduced on the thiophenolato side.…”

“…Cl. Instead, a band at 1696 cm -1 , characteristic of a C=N stretching mode,16,21,22 is observed. Neither the C=O nor the C=N stretching modes show up in the wavenumber range in the nano-sheet spectra.…”