Phosgene, caution

Since the volatile gases include sulfur tetrafluoride and thi-onyl fluoride, which possess toxicities comparable to that of phosgene, caution must be exercised in their disposal. A suitable procedure is to condense the volatile gases in a trap cooled in a mixture of acetone and solid carbon dioxide, and then to allow this material to pass slowly through an empty polyethylene bottle, which serves as a safety trap, and into a stirred aqueous potassium hydroxide solution. 

A solution of 1 molar equivalent of o-aminobiphenyl in toluene is added to a 20-30% solution of phosgene in toluene containing 6 molar equivalents of phosgene. Caution—toxic gas—use hood with good... 

Aroyl chlorides. The reaction of oxalyl chloride with aluminum chloride in CH2CI2 generates carbon monoxide and phosgene Caution /) On addition of an alkyl- or a halobenzene at 0°, p-alkyl- or p-halobenzoyl chlorides are obtained in high yield and in excellent purity. ... 

Caution Since the toxic gas phosgene is employed in this preparation, the reaction should be performed in an efficient hood. The glassware, which may be coated with a solution of phosgene, should be washed before it is removed from the hood. 

Other chlorinated solvents such as tetrachloroethylene or chloroform may be used in place of carbon tetrachloride. Caution The reaction of sulfur trioxide with chlorinated solvents has been reported to give phosgene and other toxic products. Adequate venting of all by-product gases is essential. 

Caution Phosgene is highly toxic. This preparation should be carried out in a well-ventilated hood. 

Caution Phosgene is highly toxic. Part B should be performed in an efficient hood. For a warning regarding the use of benzene, see ref. 2. 

Caution This preparation must he carried out in a hood to avoid exposure to phosgene. 

Caution Step A should be performed with gloves in an efficient hood in order to avoid contact with the toxic phosgene derivative. 

Phosgene is highly toxic gas (caution ). Phosgene is a suitable reagent for this method since it can simultaneously activate several functional groups such as amines, carboxylic acids, hydroxyl, etc. Twenty percent of COCl in toluene, almost saturated solution, is commercial available from Aldrich ( 681776). 

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. Because phosgene is volatile (bp 8°C) and highly toxic by inhalation or skin contact, is a severe lachrymator and is moisture-sensitive, this reaction should be performed in a well-ventilated hood. See general comments for choosing phosgene or related reagents elsewhere in this volume. 

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. 

CAUTION Phosgene (COCI2) is a colorless, poisonous gas or volatile liquid. This reagent should be handled with the utmost care. 

Fifteen grams of green chromic oxide (No. 7) are placed in the center of a combustion tube and the latter is placed in a tube oven with temperature control. The exit end of the tube should have an opening of at least 10mm to allow for escape of sublimed hexachloroethane, which is formed as a by-product. [CAUTION The experiment must be conducted in hood because vapors of phosgene are poisonous.)... 

CAUTION When used for extinguishing fires, phosgene, which is very poisonous, is liable to be formed.1... 

Caution Hexamethylenediamine, hexamethylene diisocyanate, and phosgene are highly toxic. Exposure to vapors or solutions containing these materials should be avoided. All operations should be conducted in a hood. 

Caution Operations prior to vacuum distillation of the product should be done in a good hood since phosgene, carbon monoxide, and hydrogen... 

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

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