Compounds with Sn-S Bonds

The tin thiols, R.SnSII, (like the hydroxides, RsSnOH), are usually unstable and disproportionate to give the ditin sulfides and H2S the only known exception appears to be tri-t-butyltin hydrosulfide, which has been prepared by the reaction shown in equation 17-1. When it is sublimed at 200-210 C/ICF4 bar it is converted into the sulfide.3 

Some organotin thiolates and sulfides have found industrial application as stabilisers for poly (vinyl chloride). Much of the work on organotin compounds of sulfur has been directed towards this end, and much of it has been published only in the patent literature. 

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Organotin compounds with Sn-S bonds can be prepared by substituation at tin by sulfur nucleophile. There are many parallels between the chemistry of compounds containing Sn-S bonds and those containing Sn-0 bonds. An important difference between them is that whereas Sn-0 bonded compounds often self-associate to give oligomers or polymers with 5-coordinate tin, the sulfur compounds show fewer tendencies to associate. The Sn-S bonds also less easily cleaved in substitution (e. g. hydrolysis) and addition reactions [54,56]. 

Both CU7 38Mn4Sni2S32 (Z = l) and CU7 07Ni4Sni2S32 (Z = l) crystallize in the cubic Fd3m space group with a= 10.4145 and 10.305(1) A respectively. The occupancies of M and Sn (which occupy the 16d sites) refine to 0.25 and 0.75 and hence were fixed in the final refinement. However in both the structures a small amount of Cu deficiency was observed in the 8 a sites. The interatomic distances in both the compounds are in accordance with the earher known compounds [17]. The ionic radii of Mn (VI, HS) is 0.83 and is larger than the size of the Ni (Vl) which is 0.69 [22]. Accordingly the Mn/Sn-S bond distance is greater than the Ni/Sn-S bond distance. 

M(II) organometallic compounds are found with cyclopentadienyl. Sn(C5H5)2 has a bent sandwich structure 2, where the stereochemical influence of the lone-pair is apparent. M(IV) organometallic compounds with M C s bonding are extremely varied and include simple tetraalkyls MR4 and compounds with Sn Sn bonds similar to those of Si and... 

Spiro-Z w(ethanedithiolate), (CH2CH2S)2Sn, is also associated, 101, via pairs of Sn- -S bonds (Sn- -S 3.764 and 3.811 A compared with Sn-S 2.405 and 2.388 A) [261] and the Mossbauer spectrum of the compound also indicates sixfold coordination at tin [262], 2,2-Dialkyl-1,3,2-oxathiastannolanes are associated only through S - 0 bonds (see Section 3.3.1) illustrating the stronger Lewis base character of oxygen towards tin [263]. 

The resistance of the E14-S bond in cyclotrimetallathianes toward nucleophilic reagents, for example, water and alcohol,62 increases on going from the silicon compounds to the corresponding germanium and tin derivatives. This is due, most likely, to the fact that the reaction of less nucleophilic ylides with phenyl groups at the phosphorus atom with trithianes (R2MS)3 (M = Ge, Sn) occurs slowly and is impeded by several side processes. 

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