Sulfur pyramidal geometry

Verify, by making molecular models, that the bonds to sulfur are arranged in a trigonal pyramidal geometry in sulfoxides and in a tetrahedral geometry in sulfones. Is phenyl vinyl sulfoxide chiral What about phenyl vinyl sulfone ... 

In nickel and palladium dithiobenzoato complexes, four-membered chelate rings are formed (366), whereas, in the corresponding phenyl-dithio acetates [M2(S2CCH2Ph)4], the dithio ligands act as bridging groups between the two metal atoms, with the formation of binuclear units (367). The molecular structure of the latter compounds shows that each metal atom is coordinated to four sulfur atoms and to the other metal atoms in a square-pyramidal geometry. Other evidence for... 

The tetranuclear sulfur and selenium derivatives [E(AuPPh3)4]2+ show a square pyramidal geometry with the chalcogen atom in the apical position [241]. These cations dimerize in the solid state through Au-E interactions (Figure 1.40). Further auration of sulfur and selenium to give the penta- and hexa-nudear species has been achieved and trigonal bipyramidal and octahedral structures have been proposed [242]. 

With 3-hydroxyquinazoline-4(3//)-thiones (HQ) (Scheme 20 Z = S, Y = NOH), the ESR spectra were explained assuming equilibria (63).848 Compounds isolated, [VOQ2], involved sulfur and oxygen atoms in a square pyramidal geometry. 

Metal disulfides (MS2) and metal dichalcogenides (MS4) (metal M = Cd, Mo, Zr, Ti, Nb, Ta, or Sn) are lamellar colloids with strong M—S bonds within the layers and weak van der Waals interactions between the layers. Each metal atom in these lamellae is surrounded by six sulfur anions with an approximate octahedral coordination geometry. Each sulfur anion is, in turn, coordinated to three metal atoms with a trigonal pyramidal geometry [50], Certain cationic species or polymers are adsorbed onto these surfaces via intercalation or exfoliation [51,52],... 

The characterization of complexes 55-58 involved IR, H NMR and 31P NMR spectroscopy and X-ray crystallographic analysis in the case of 55 and 56 [58]. The complexes are five-coordinate, adopting a distorted square-pyramidal geometry. The oxo group occupies the axial position and the equatorial plane is defined by the tridentate dianionic chelators and by the sulfur atom of the monothiolate. 

Aldehyde oxidoreductase and XO/dehydrogenase share the same approximate square-pyramidal geometry at the Mo atom created by an equatorial dithiolene chelate, an apical sulhdo ligand, an oxo ligand trans to one dithiolene sulfur in the equatorial plane and a hydroxo or water group in the remaining equatorial site. 

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