Dimethyltin chloride

Dimethyltirf. Acute toxicity studies were identified for dimethyltin for algae, invertebrates, and fish. Chronic NOECs were available for algae and invertebrates. A chronic NOEC of 0.2 mg/1 for dimethyltin chloride in Daphnia magna was the lowest reported result the result has been corrected to the chloride salt for comparison with the majority of test results. Since there were no long-term test results available for fish, it was necessary to apply an uncertainty factor of 50 to the critical study. 

The methyl-[14C]-dimethyltin chloride was used to compare the performance of packed and megabore capillary columns in a gas chromatographic analysis for separating mixtures of a carbon-14 labelled trimethyllead chloride, tetramethyltin, dimethyltin dichloride and methyltin trichloride. The megabore column was able to separate all four methyltin compounds quickly, i.e., before the tetramethyltin decomposed into trimethyltin chloride and dimethyltin dichloride (equation 47), a reaction which did occur on the packed columns. Thus, the megabore column enabled the determination of the precise distribution of the various methyltin compounds in an environmental sample. The packed columns, on the other hand, could not separate dimethyltin dichloride and the methyltin trichloride and allowed significant decomposition of the tetramethyltin during the 15 minutes the analysis required. 

Tin chlorides react with diazomethane to give chloromethyl derivatives, e.g., (chloromethyl)dimethyltin chloride in good yield from dimethyltin dichloride 386... 

Alkyltin Intermediates. For the most part, organotin stabilizers are produced commercially from the respective alkyltin chloride intermediates. There are several processes used to manufacture these intermediates. The desired ratio of monoalkyltin trichloride to dialkyltin dichloride is generally achieved by a redistribution reaction involving a second-step reaction with stannic chloride [tin(IV) chloride]. By far, the most easily synthesized alkyltin chloride intermediates are the methyltin chlorides because methyl chloride reacts directly with tin metal in the presence of a catalyst to form dimethyltin dichloride cleanly in high yields (21). Coaddition of stannic chloride to the reactor leads directly to almost any desired mixture of mono- and dimethyltin chloride intermediates ... 

Acetyloxy)chlorodimethylstannane, loci. Dimethyltin chloride acetate. (Acetato-O)chlorodimethylstannane [38186-24-2]... 

Dimethyltin bis(acetylacetonate), see Sn-00244 Dimethyltin bis(A, A -diethyldithiocarbamate), see Sn-00250 Dimethyltin bis(diethyldithiophosphinate), see Sn-00212 Dimethyltin bis(A, A -dimethyldithiocarbamate), see Sn-00161 Dimethyltin bis(fluorosulfonate), see Sn-00014 Dimethyltin bis(isothiocyanate), see Sn-00045 Dimethyltin bis(methylselenide), see Sn-00080 Dimethyltin bis(methylsulfinate), see Sn-00073 Dimethyltin bis(methylthiolate), see Sn-00076 Dimethyltin bis(oxinate), see Sn-00347 Dimethyltin bromide hydride, see Sn-00022 Dimethyltin chloride acetate, see Sn-00049 Dimethyltin chloride methoxide, see Sn-00031... 

Physica.1 Properties. Physical properties of some typical diorganotin compounds are shown in Table 6. The diorganotin chlorides, bromides, and iodides are soluble in many organic solvents and, except for dimethyltin dichloride, are insoluble in water. 

Dimethyltin dichloride is used in the glass industry as an alternative to stannic chloride for coating glass with a thin film of stannic oxide 562). The dialkyltin compound vapor is brought into contact with the glass surface at temperatures of 500-600°C, where decomposition and oxidation occurs. 

Dimethyltin dichloride (hRf 15-20), trimethyltin chloride (h/ f 55-60), dibutyltin dichloride (h/ f 70-75) and tributyltin methoxide (h/ f 80-85) appeared in long-wavelength UV light (X = 365 nm) as yellow fluorescent chromatogram zones on a dark background. The detection limits (calculated as Sn) lay between 5 and 10 ng (dimethyltin dichloride, dibutyltin dichloride, tributyltin methoxide) and 50 ng (trimethyltin chloride) substance per chromatogram zone. 

Fig. 1 Fluorescence scan of a chromatogram track with 100 ng substance (calculated as Sn) each per chromatogram zone 1 = dimethyltin dichloride, 2 = trimethyltin chloride, 3 = dibutyltin dichloride, 4 = tributyltin methoxide.

Reliable lifetime TDI values cannot be derived, since long-term studies at the appropriate doses and in the appropriate species are not available. Medium-term exposure TDIs for the estimation of risk were estimated (as the chlorides) as 0.0012 mg/kg body weight for monomethyltin and dimethyltin based on neurotoxicity, 0.003 mg/kg body weight for dibutyltin based on immunotoxicity, and 0.002 mg/kg body weight for dioctyltin, also based on immunotoxicity. No reliable TDI could be derived for monobutyltin or monooctyltin. 

The direct and indirect assessment of the aneuploidy-inducing potency of a number of organotin compounds was reported by Jensen et al. (1991a). The effects of dimethyltin dichloride, diphenyltin dichloride, trimethyltin chloride, tributyltin chloride, and triphenyl-tin chloride at 10 -10 mol/1 on chromosomal contractions in cultures of human peripheral lymphocytes were investigated. Diphenyltin dichloride, trimethyltin chloride, tributyltin chloride, and triphenyl-tin chloride appeared to be very strong inducers of chromosomal supercontraction, indicating that these compounds induce aneuploidy, probably by affecting... 

One of six workers died 12 days after exposure to a mixture of half dimethyltin dichloride and half trimeth-yltin chloride vapour during cleaning of a cauldron at a chemical plant in Germany in 1981. Maximum exposure time was 1.5 h over a 3-day period no estimates of exposure concentration were made. Symptoms preceding death included excretion of high levels of tin in the urine, respiratory depression, and coma (Rey et al.,... 

Effects on terrestrial organisms are reported only for mixtures of mono- and dimethyltin compounds (50 50 and 25 75), with 14-day LC50 values of 320 and >1000 mg/kg (as chloride), respectively, in the earthworm (Eisenia foetida), respective NOECs were 100 and 1000 mg/kg (as chloride) (Wilbury, 1995a,b, 1996). 

Dimethyltin dichloride can be synthesized from methyl chloride, tin(II) chloride and molten tin. The reaction proceeds in high yields in NaAlCLt melt359. High yields in tri-organotin halides are also obtained from tin and lower alkyl halides, provided an equimolar amount of halide is added to the reaction medium360. 

The various tetraalkyltin compounds were then identified and quantitated by GC MS and gas chromatography-atomic absorption analyses. The results indicated that tin(II) chloride in the simulated sea water was converted into methyltin trichloride and dimethyltin dichloride. The tin(IV) chloride, on the other hand, only formed methyltin trichloride. No trace of trimethyltin chloride was found from either tin(II) or tin(IV). The maximum amount of methyltin trichloride was formed near pH = 6 and at a salinity of 28%. The rate expression for the reaction is... 

Hamasaki and coworkers87 investigated the genotoxicity of 14 organic tin compounds (methyl-, butyl- and phenyltins) and inorganic tin (SnCU) on Escherichia coli and on Bacillus subtilis. Dibutyltin dichloride, tributyltin chloride, tributyltin chloride, bis(tributyl-tin)oxide, dimethyltin dichloride and trimethyltin chloride were all found to be genotoxic. 

The recovery of methyltins from sediments was tested by using anoxic, sulphitic clay sediments from a mid-salinity region of Chesapeake Bay. Monomethyltin (11.2ng) and dimethyltin (11.5ng) were completely recovered from sediment. However, recovery of lOng of trimethyltin chloride from sediment was only about 70%. 

The effect of added salts on the rate coefficient for reaction (23) (R = Me) was also studied. Results are collected in Table 23 and show that, whereas sodium perchlorate has a marked accelerating effect (as it does also on the analogous substitution of dimethyldiethyltin), the addition of chloride ion strongly retards the substitution. It was suggested32 that reaction (23) actually proceeds through the solvated Me2Sn2+ ion, formed by the dissociation of dimethyltin dichloride... 

A dilute solution of dimethyltin methoxide chloride, Me2Sn(OMe)Cl, in dichloromethane shows (69) two 119Sn signals at +126 and —90 ppm. This is compatible with the presence of an equilibrium between the simple tetrahedral monomer [6a] and the symmetrical dimer [6b]... 

Organotin Compounds. Respiratory depression requiring artificial ventilation occurred in three of six chemical workers. The exposure duration was a total of 1.5 hours over a 3-day working period to a mixture containing half dimethyltin and half trimethyltin chloride (Rey et al. 1984). Although the two surviving workers, who were the most severely affected, developed permanent neurological disabilities, respiratory problems did not persist. 

Environmental Tin Chlorides of dimethyltin, trimethyltin, dibutyltin and tributyltin diphenyltin and triphenyltin Micellar chromatography 24-51 pg as Sn Inoue et al. (1995)... 

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