Organotin standards

Methyltin trichloride, dimethyltin dichloride, and trimethyltin hydroxide or chloride were obtained from Research Organic/Inorganic Chemical Corporation (Sun Valley, Calif.) for use as the organotin standards. Stock solutions from 500 to 1000 parts per million in 95% ethanol were prepared and proved to be stable for four to five weeks. Serial dilutions, usually 1 100 of the stock solutions, were made fresh daily in deionized water when calibration was needed. Both the inorganic and methyltin standards were delivered with 10 yl size syringes. 

The current OSHA TLV standard for exposure to all organotin compounds is 0.1 mg of organotin compounds (as tin)/m air averaged over an 8-h work shift (192). NIOSH has recommended a permissible exposure limit of 0.1 mg/m of tin averaged over a work shift of up to 10 h/d, 40 h/wk Reference 193 should be consulted for more detailed information. Additional information on the health effects of organotin compounds is given in Reference 48. 

Catenation is well established in organotin chemistry and distannane derivatives can be prepared by standard methods (see Ge, p. 396). The compounds are more reactive than organodiger-manes e.g. Sn2Meg (mp 23°) inflames in air at its bp (182°) and absorbs oxygen slowly at room temperature to give (Me2Sn)20. Typical routes to higher polystannanes are ... 

NIOSH (1976) Criteria for a recommended standard — occupational exposure to organotin compounds. Report to National Institute for Occupational Safety and Health, Cincinnati, OH, by SRI International, Menlo Park, CA (NIOSH-77-115 NTIS No. 274766). 

TABLE 3. Standard enthalpies of formation of organotin compounds (kJ mol )... 

OSHA TLV toxicity standard, for organotin compounds, 24 831 Oslo crystalizer, 8 139 OSME method, 11 520-521 Osmitrol, 5 169... 

Ebdon et al. [88] have discussed a programme to improve the quality of analytical results in the environmental monitoring of organotin compounds. They discuss the evolution of a sensitive, reliable and robust analytical method for the determination of tributyltin, with emphasis on the difficulties of determining it at the ng per litre levels at which it was usually encountered, more especially as other forms of tin frequently occurred together at similar levels. The preparation of a standard reference sample, for use in interlaboratory comparative determinations, under the aegis of the Bureau of Community Reference of the EU is described, and plans for subsequent distributions of blank, artificially spiked, and genuinely affected sediments are sketched. 

Organotin compounds enriched from a diethylether extract of a snow sample collected from the city of Gdansk, Poland and analyzed are shown in Fig. 22 b, c [286]. Gas chromatography with atomic emission detection (GC-AED) run in the chlorine and tin channels, respectively, revealed the presence of tributyltin chloride and this was subsequently confirmed by GC-MS and GC-AED analyses of an internal standard solution (e.g., 1-chlorooctane) of that compound. Quantification was based on the response to chlorine (wavelength 479 nm) in the AED system, and a detection limit of 0.5-1 ng/1 was achieved for all the reference substances. 

National Institute for Occupational Safety and Health Criteria for a Recommended Standard. .. Occupation Exposure to Organotin Compounds. DHEW (NIOSH) Pub No 77-115, pp 26-105. Washington, DC, US Government Printing Office, 1976... 

The syntheses of dithioacetals are generally straightforward [43]. Standard methods may be unselective for multifunctional molecules. Therefore, new procedures have been developed. It has thus been reported that 1,3-dithianes are readily synthesized by reaction of aldehydes, ketones or acetals with 2-stanna-l,3-dithianes under catalysis of organotin triflates [45]. These odourless reagents are prepared from dialkyldichlorotin and 1,3-propanedithiol. 

NIOSH. 1977. A recommended standard for occupational exposure to. .. organotin compounds. Cincinnati, OH U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health. 

Unger et al. [217] determined butyltins in non saline water by gas chromatography with flame photometric detection and confirmation by mass spectrometry. The sample was extracted with tropalone in //-hexane and organotin compounds derivatised with n-hexyl magnesium bromide to form tetraalkyltins. The n-hexyl derivatives of methyltin and butyltin species were easily separated and quantified relative to an internal standard (triphenyltin chloride) which was not found to be present in environmental samples and did not interfere. 

R. A. Cummins and P. Dunn, The Infrared Spectra of Organotin Compounds, p. 6.9-3, Australian Defence Scientific Service, Defence Standards Laboratories, Maribrynong, Victoria, 1963. 

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