Group IV Sulfides

Tin(IV) sulfide can be prepared by hydrogen sulfide precipitation of Sn(IV) from solution, to produce a microcrystalline material that is contaminated with oxide. Mosaic gold is a crystalline form of tin(IV) sulfide prepared by high-temperature sublimation procedures. Mosaic gold is the reported product of heating mixtures of (1) tin and sulfur (2) tin, sulfur, and ammonium chloride (3) tin, sulfur, mercury, and ammonium chloride (4) tin(II) oxide, sulfur, and ammonium chloride (5) tin(II) chloride and sulfur (6) tin(II) sulfide, tin(II) chloride, and sulfur.  

Titanium(IV) sulfide, zirconium (IV) sulfide, hafnium(IV) sulfide, and tin(IV) sulfide constitute a group of isostructural compounds that can be prepared by similar methods. A 

---

Group IV cations have soluble chlorides and sulfides, so they are still in solution at this point. The alkaline earth cations (Mg2, Ca2+. Ba2+) are precipitated as carbonates... 

Layered sulfides predominate in Groups IV to VII except for MnS, which is isotropic. The main structural feature of this class is a strong chemical anisotropy that greatly affects their catalytic properties. In the molybdenite structure (MoS2), the metal is in trigonal prismatic coordination. Other layered sulfides are octahedrally coordinated or distorted octahedrally coordinated (ReS2) with the metal surrounded by six sulfur atoms. It should also be noted that some TMS sulfides have structures that fall in between isotropic and layered sulfides. Rh2S3 is an example and others are completely amorphous, such as IrSt and OsSr. 

Catalytic oxidations of sulfides were carried out in 1,2-dichloroethane with cumyl hydroperoxide by using 10 mol % of the catalyst. The best enantioselectivity was achieved with complex 6c. However, sulfone was always produced as byproduct of the reaction. Even with a limited amount of hydroperoxide, the sulfone formation could not be avoided. For example, the reaction of methyl p-tolyl sulfide using 0.5 mol equiv. of cumyl hydroperoxide with respect to sulfide gave a 62 38 mixture of the corresponding (.S j-sulfoxide and sulfone. The reaction of benzyl phenyl sulfide led to the formation of (5)-sulfoxide (84% ee) and sulfone ([sulfox-ide]/[sulfone] = 77 23). It was established that sulfone was produced from the early stages of the reaction. It was also demonstrated that some kinetic resolution of the sulfoxide cooperated with the enantioselective oxidation of the sulfide. A unique feature of this oxidation system, as compared to those using various Ti(IV)/(DET) complexes, is the insensitivity of the enantioselectivity (40-60% ee at 0°C) to the nature of the alkyl group of sulfides Ar-S-alkyl. 

Cadmium sulfides and selenides group Tin sulfides group Tungsten group Berndtite Cassiterite Chromium tin oxide Cobalt tin oxide Copper tin oxide Herzenbergite Lead antimony tin oxide Lead tin oxide Lead tin silicon oxide Ottemannite Romarchite Tin chromate Tin(IV) oxide Tin(IV) sulfide Bronze colours-, Egyptian blue Lead tin yellow Mosaic gold Mosaic silver, Tin white... 

The highly regio- and diastereoselective addition of an alkyl and an arylthio group to an olefinic double bond ( carbosulfenylation ) is achieved with arenesulfenyl chlorides and alkyl-chloro-titanium(IV) species (Reetz reagent, from R2Zn/TiCU 5 1 M. T. Reetz, 1987, 1989), Use of the more bulky 2,4,6-triisopropylbenzenesulfenyl chloride improves the yield of the highly versatile alkyl aryl sulfide products. 

---