93142-38-2Relevant academic research and scientific papers
Supramolecular Paradigm for Capture and Co-Precipitation of Gold(III) Coordination Complexes
Shaffer, Cassandra C.,Liu, Wenqi,Oliver, Allen G.,Smith, Bradley D.
, p. 751 - 757 (2021)
A new supramolecular paradigm is presented for reliable capture and co-precipitation of haloauric acids (HAuX4) from organic solvents or water. Two classes of acyclic organic compounds act as complementary receptors (tectons) by forming two sets of directional non-covalent interactions, (a) hydrogen bonding between amide (or amidinium) NH residues and the electronegative X ligands on the AuX4?, and (b) electrostatic stacking of the electron deficient Au center against the face of an aromatic surface. X-ray diffraction analysis of four co-crystal structures reveals the additional common feature of proton bridged carbonyls as a new and predictable supramolecular design element that creates one-dimensional polymers linked by very short hydrogen bonds (CO???OC distance ?). Two other co-crystal structures show that the amidinium-π???XAu interaction will reliably engage AuX4? with high directionality. These acyclic compounds are very attractive as co-precipitation agents within new “green” gold recovery processes. They also have high potential as tectons for controlled self-assembly or co-crystal engineering of haloaurate composites. More generally, the supramolecular paradigm will facilitate the design of next-generation receptors or tectons with high affinity for precious metal square planar coordination complexes for use in advanced materials, nanotechnology, or medicine.
