Selective Gold Recovery and Catalysis in a Highly Flexible Methionine-Decorated Metal–Organic Framework

TLDR: A novel chiral 3D bioMOF exhibiting functional channels with thio-alkyl chains derived from the natural amino acid l-methionine has been rationally prepared, showing high activity as heterogeneous catalyst for the hydroalkoxylation of alkynes, further expanding the application of these novel hybrid materials.

Abstract: A novel chiral 3D bioMOF exhibiting functional channels with thio-alkyl chains derived from the natural amino acid l-methionine (1) has been rationally prepared. The well-known strong affinity of gold for sulfur derivatives, together with the extremely high flexibility of the thioether “arms” decorating the channels, account for a selective capture of gold(III) and gold(I) salts in the presence of other metal cations typically found in electronic wastes. The X-ray single-crystal structures of the different gold adsorbates AuIII@1 and AuI@1 suggest that the selective metal capture occurs in a metal ion recognition process somehow mimicking what happens in biological systems and protein receptors. Both AuIII@1 and AuI@1 display high activity as heterogeneous catalyst for the hydroalkoxylation of alkynes, further expanding the application of these novel hybrid materials.