Organotin thiolates

The organotin thiolates are more readily prepared, and are less reactive, than either the alkoxy or tW amino compounds, and the al-kynylthiyltin compounds Me3SnSC=CPh, MesSiC CSSnMes, and Me3CC=CSSnBu3 have recently been prepared by extension of the established, general methods (229). 

A recent attempt to prepare the bis(ethylenedithio)tetrathiafulvalene derivatives fused with a 1,4-dioxane ring, viz. (89), by the Me Al-promoted reaction of organotin thiolate (87) with ester (88) was unsuccessful instead the reaction resulted110 in the production... 

Organotin thiolate complexes such as the title compound are useful reagents for the synthesis of transition metal complexes with RS ligands. Examples of this use are given in the procedures that follow this synthesis. 

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. 

The organotin thiolates (mercaptides) are usually prepared by substitution by a sulfur nucleophile at a tin centre. Suitable pairs of reactants are (1) thiol and tin oxide, alkox-ide, or amide, (2) thiol and tin halide in the presence of a base such as sodium hydroxide, sodium carbonate, ammonia, or triethylamine, or (3) metal thiolate and tin halide. Examples are shown in equations 17-20,33 17-21,33 and 17-22,34 and some of the common products are listed in Table 17-2. 

The organotin thiolate stabilisers appear to perform at least a dual function.5-7 First they exchange the chloride at the allylic sites to give an allyl mercaptan which is thermally more stable and does not act as a site for initiating the elimination. 

Thiolato derivatives of main-group metals provide an interesting contrast to those of the transition metals, since despite the industrial application of compounds such as organotin sulfides, much remains to be done in the study of the chemistry of these interesting compounds. Methods for the preparation of organotin thiolates and selenolates have been reviewed, as have their physical and chemical properties. The preparation of tris(benzenethiolato)-indium by the reaction of InClj with NaSCgHj in methanol has recently been described, as have the properties of this compound. ... 

CF3)2PSP(CF3)2 and Me3SiCl. Conformational isomerism in cyclotrisil-thianes has been studied by n.m.r. Tetra(methylgermanium) hexa-sulphide has been shown by A -ray crystallography to possess an adamantane-t) structure (Figure 19). The mean Ge—C and Ge—S bond distances are 1.922 A and 2.218 A, respectively. Vibrational spectra for organotin thiolates and sulphides - and for the compounds M(SR)4 (M = Si, Ge, or Sn) have been reported. 

Also, the non-coupling syntheses are applied for the preparation of unsymmetrical tetrachalcogenafulva-lenes, in which the organotin thiolates or selenolates react with esters in the presence of Lewis acids, such as trimethylaluminum (Mc3Al), as outlined in Scheme 3.14(b), for the preparation of DMET (2b -7c) [275, 291]. The Lewis acids TiCU, Me2AlCl etc., can be used, but Me3Al gives the best results. 

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