A single-crystal 3D Zn-tetrathiolate connected metal–organic framework

Abstract

Due to thiolate's fast and robust coordination, crystallographically resolved thiolate-ligated metal–organic frameworks (MOFs) are hard to obtain. Following the previous success of the masked synthetic strategy to achieve single-crystal Pb-thiolate connected MOFs, thioester-protected hexathiotriphenylene (HVaTT) was employed in this work to assemble with a Zn(II) centre to yield the first example of a first-row transition-metal based crystallographically resolved metal-tetrathiolate connected MOF, HTT-Zn. HTT-Zn features a 3D anionic framework connected by tetrahedral [ZnS₄] nodes with 3-fold interpenetration and windmill-like topology. Thanks to the anionic nature, HTT-Zn demonstrates a fast colorimetric response (from yellow to black) to the positively charged toxic pollutant, paraquat, and potentially serves as a naked-eye sensor for paraquat. Isolation of HTT-Zn proves masked synthesis as a general approach and adds a new dimension to explore metal-thiolate-based MOFs.