Coordination polymers of copper(II) with some dicarboxysiloxane ligands

Abstract

Several new coordination polymers of copper(II) with different carboxylate ligands containing siloxane units were synthesized by equilibrium polycoordination reactions of copper(II) acetate with the proper dicarboxylic acid (i.e. 1,3-bis(3-carboxypropyl)tetramethyldisiloxane, a,o-bis(3-carboxypropyl)oligodimethylsiloxane, and 1,3-bis(sebacomethyl)tetramethyldisiloxane) in solution (methanol), at room temperature. Some variations in the feed molar ratios were made. The resulting polymers having a polycoordination degree between 5 and 71 are soluble in a wide range of common organic solvents. The formation of polymers was proved by IR and UV±VIS absorption spectroscopy. The thermal behaviour of the coordination polymers was analysed by thermogravimetry in air. The silicon and copper contents and inherent viscosities were also determined.

Linear Terpyridine‐Ruthenium(II) Poly(ethylene glycol) Coordination Polymers

“…[5,6,20] Thus, the polyelectrolyte effect of the compounds was investigated. The viscosity experiments were repeated in solutions of tetrabutylammonium tetrafluoroborate (20 mmol/L for 4b; 50 mmol/L for 3).…”

Free radical grafting of itaconic acid and glycidyl methacrylate onto PP initiated by organic peroxides

“…The presence of a siloxane segment within a polymeric ligand can confer improved solubility on coordination polymers. Such an effect has been emphasized in our previous studies 28, 29. Another important feature of siloxane polymers is their unusually high gas permeability 30…”

Hydrophobic, amorphous metal–organic network readily prepared by complexing the aluminum ion with a siloxane spaced dicarboxylic acid in aqueous medium

“…The particularity of this ditopic ligand lies in the containment of the tetramethyldisiloxane moiety with high flexibility conferred by the siloxane linkage and hydrophobicity conferred by the methyl groups (known as the most hydrophobic organic groups) attached to the silicon atoms. 1,3‐Bis(carboxypropyl)tetramethyldisiloxane was prepared according to the procedure previously reported by us since 1999 although, meanwhile, the compound has become commercially available at Gelest, Inc., Morrisville, PA. We have previously used this acid in the preparation of complexes of metals, most of which are crystalline and structurally characterized, but the acid as such, although crystalline having a melting point around 50 °C, has never been isolated alone as crystals suitable for crystallographic analysis. In the context of the study presented in this manuscript, when crystallization of the network was attempted by the addition of formic acid as a framework modulator, according to Wißmann et al ., the disiloxanic acid liberated from the salt form by the stronger formic acid unexpectedly separated itself in the form of crystals perfectly suited for single crystal X‐ray diffraction analysis.…”

“…While Davies et al . synthesized and used as ligands hexa(4‐carboxyphenyl)disiloxane molecules, we tried to use a longer and more flexible dicarboxylic acid, 1,3‐bis(carboxypropyl)tetramethyldisiloxane, as a ligand for metals or for the construction of more complex structures …”