On the Chalcogenophilicity of Mercury: Evidence for a Strong Hg−Se Bond in [Tm^But]HgSePh and Its Relevance to the Toxicity of Mercury

Abstract

One of the reasons for the toxic effects of mercury has been attributed to its influence on the biochemical roles of selenium. For this reason, it is important to understand details pertaining to the nature of Hg-Se interactions and this has been achieved by comparison of a series of mercury chalcogenolate complexes that are supported by tris (2-mercapto-1-t-butyl-imidazolyl) ]CdEPh, the Hg-EPh bonds are actually shorter than the corresponding Cd-EPh bonds, an observation which indicates that the apparent covalent radii of the metals in these compounds are dependent on the nature of the bonds. Furthermore, the difference in Hg-EPh and Cd-EPh bond lengths is a function of the chalcogen and increases in the sequence S (0.010 Å) < Se (0.035 Å) < Te (0.057 Å). This trend indicates that the chalcogenophilicity of mercury increases in the sequence S < Se < Te. Thus, while mercury is often described as being thiophilic, it is evident that it actually has a greater selenophilicity, a notion that is supported by the observation of facile selenolate transfer from zinc to mercury upon treatment of [Tm Bu t ]HgSCH 2 C(O)N(H)Ph with [Tm Bu t ]ZnSePh. The significant selenophilicity of mercury is in accord with the aforementioned proposal that one reason for the toxicity of mercury is associated with it reducing the bioavailability of selenium.

Dinuclear platinum complexes with designer thiolate ligands from the monoalkylation of [Pt2(μ-S)2(PPh3)4]

“…Some of these complexes were previously identified in our earlier screening study [5]. Although metal complexes of the thiolate ligands PhNHC(O)CH 2 S À [15,16] and MeO 2 CCH 2 S À [17][18][19] are well known, and the thiols PhC(O)CH 2 SH [20] and EtO 2 CCH 2 C(O)CH 2 SH [21] are reported, the other thiolate ligands (or the free thiols) contained in complexes 3e-3o appear to be new ligands.…”

β-Carboline-functionalized dithioacetal as Hg2+-selective fluorescence probe in water

“…The mercury ion Hg 2+ , one of the more severe environmental pollutants, is very harmful to the human body [4]. When absorbed, Hg 2+ damages the brain, kidneys, and endocrine system [5]. Therefore, the rapid and selective detection of Hg 2+ is very important.…”

Highly Selective Anionic Counterion‐based Fluorescent Sensor for Hg2+ by Grafted Conjugated Polyelectrolytes

“…Mercury is one of the most notorious heavy metals [1] which causes serious environmental and health problems. [2] Owing to such concerns, interest in designing and constructing chemosensors with extremely high selectivity and sensitivity for Hg 2þ has been experiencing an upsurge.…”