Methyl isocyanate toxic potential

New Chemistry for the Preparation of Temozolomide. The three main disadvantages of the present synthesis (Scheme 14) were outlined earlier. Of these only the first two, the potential explosivity of the diazonium intermediate (XXIV) and the toxicity of methyl isocyanate, can be addressed. In the first, the handling of the potentially explosive intermediate is best accommodated by ensuring that this material remains wet at all times. Thus, avoiding the preparation and use of methyl isocyanate became the primary objective. 

Isoouanates. Various isocyanates are employed in the polymer industry. These compounds are powerful irritants and they are highly toxic. Of particular interest are methylene-di-paraphenylene isocyanate (MDI) and toluene-2,4-diisocyanate (TDI). Various alkyl isocyanates (e.g., methyl, ethyl, propyl, butyl, and cyclohexyl) derivatives may also be of current interest with respect to potential occupational health hazards. Simultaneous analysis of MDI and TDI by HPLC has been accomplished by a modification of the method of Dunlap et al. (28). Air samples are collected in impingers containing p-nitrobenzyl-n-... 

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