Fume hoods phosgene

Note Phosgene is eery hazardous and only professional chemists working with a fume hood should even think about using this method. It can be dissolved in a weighed container of DMF (dimethylformamide) and a second weighing will give the phosgene concentration. 

Caution. Phosgene is a highly toxic gas that reacts with water to form HCl and has a characteristic odor of freshly mown hay. It is necessary to carry out this portion of the reaction using standard Schlenk techniques and in a well-ventilated fume hood. Unreacted phosgene can be neutralized with aqueous base. 

Caution. CO gas and phosgene (which may be formed as a volatile byproduct in the first step) are highly toxic. Appropriate personal protection must be adopted and all manipulations must be carried out in a highly efficient fume hood. 

Caution. Highly toxic carbonyl chloride (phosgene) may be formed as a by-product and therefore use of an efficient fume hood is mandatory. 

Isocyanates are hazardous. Prolonged exposure to their vapors has been associated with chronic airway disorders. Phosgene is very hazardous and should be handled only in a well-ventilated fume hood. PI Triphosgene and sodium azide are toxic. 

Caution This reaction should be carried out in a fume hood since phosgene is an insidious poison. 

In case of the accidental release of phosgene gas, such as liom a leaking cylinder or associated apparatus, evacuate the area and eliminate the source of the leak if this can be done safely. Remove cylinder to a fume hood or remote area if it cannot be shut off. In the event of a spill of a phosgene solution, soak up the solution with a spiU pillow or absorbent material, place in an appropriate container, and dispose of properly. Full respiratory protection and protective clothing wiU be necessary in the event of a spill or release in a confined area. 

Handling, Storage, and Precautions very unstable to water and silica gel however, it can be handled in air. It is stable for one month if stored at —25 °C. Since phosgene is used in preparing this reagent, preparation should be in a working fume hood and extreme caution is required. 

Handling, Storage, and Precautions highly toxic gas avoid contact or inhalation there may be a delay of several hours before symptoms of exposure develop (pulmonary edema) keep container tightly closed and well-ventilated excess phosgene should be vented into a water-fed scrubbing tower. Use in a fume hood. 

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