Trichloramine

Subsequently it was found that trimethylsilyl azide in triflic acid is a more efficient and improved reagent for aminations (169). Amination of toluene in the presence of trichloramine—A1 CL proceeds predominantly at the / -position. 

Prepared by the latter route, decomposition is - 10% in 24 h. This reaction involves direct Cl transfer to NH2CI via the intermediate NH CE NH2CI hydrolysis playing Htde or no role. The presence of NH" 4 improves stabiUty by reacting with HOCl which tends to increase decomposition (39). Trichloramine also increases decomposition, whereas NH2CI has Httle effect. Dichloramine is useful for preparation of diazirine (40). 

Hypochlorous acid reacts very rapidly and quantitatively with a slight excess of free ammonia forming monochloramine, NH2CI, which reacts at a slower rate with additional HOCl forming dichloramine, NHCI2. Trichloramine is formed when three moles of HOCl are added per mole of ammonia between pH 3—4 (100). Hypochlorous acid in the form of chlorine or hypochlorite is used in water treatments to oxidize ammonia by the process of break-point chlorination, which is based on formation of unstable dichloramine. The instabiHty of NHCI2 is caused by presence of HOCl and NCl (101,102). The reaction is most rapid at a pH of about 7.5 (103). Other nitrogen compounds such as urea, creatinine, and amino acids are also oxidized by hypochlorous acid, but at slower rates. Unstable iV-chloro compounds are intermediates in deammination of amino acids (104,105). 

Chlorine Nitride. (Nitrogen Trichloride, Trichloramine, or Stickstofftrichlorid in Ger). 

And finally, trichloramines are formed when chlorine reacts further with the dichloramines. 

Trichloramine is the most irritant of the chloramines together with dichloramine it is largely responsible for the chlrorine odours and eye irritation. 

Caution The reactions should he carried out in a hood behind a protective screen since trichloramine is noxious and potentially explosive however, no difficulties from decomposition have been encountered under the conditions described. 

A. Trichloramine. A mixture of 600 ml. of water (Note 2), 900 ml. of methylene chloride (Note 3), and 270 g. (1.32 moles) of calcium hypochlorite (Note 4) is cooled to 0-10° in a 3-1., three-necked, vented flask equipped with a stirrer, a thermometer, and a dropping funnel. A solution of 66.0 g. (1.23 moles) of ammonium chloride in 150 ml. of concentrated hydrochloric acid and 450 ml. of water is added dropwise with stirring over a 1-hour period at 0-10°. After an additional 20 minutes of stirring, the organic layer is separated, washed with three 200-ml. portions of cold water, and dried over anhydrous sodium sulfate. The yellow solution is filtered, and the trichloramine concentration is determined by iodometric titration (Note 5). 

Cooling is accomplished with either an ice-salt bath or preferably a dry ice-acctonc bath. The time of addition can be reduced to 1 hour by use of the latter. However, if the temperature is much below that designated, unchanged trichloramine accumulates, resulting eventually in an uncontrollable reaction. 

Purging with nitrogen results in some increase in yield. If the flow is too vigorous, trichloramine is lost by volatilization. 

Tricerium tetrasulfide, 5 677 Tricesium oxide, 5 700 Trichlor, 26 188 Trichloramine, 13 103 Trichlorfon... 

Chlorinated swimming pool exposures have also been Unked with respiratory effects, including asthma [140, 150-152]. Trichloramine, which is formed by the reaction of chlorine with urea (from sweat and urine), has been suspected in these cases of asthma. In addition to sweat and urine, pool waters also contain other DBF precursors, such as skin cells, hair, and lotions/sunscreens. 

In the second, >100 DBFs were identified in indoor chlorinated and brominated pools, including many nitrogenous DBFs (haloamides, halonitriles, haloanilines, haloamines, haloanisoles, and halonitro-compounds), likely due to the nitrogen-containing precursors from swimmers (urine, sweat, etc.) [143]. Trichloramine and THMs were also measured in the pool air [143]. Nitrosamines have been measured in chlorinated pools and hot tubs, up to a maximum of429 ng/L... 

Levels observed were up to 500 x greater than the level (0.7 ng/L) associated with a one in a million lifetime cancer risk. Volatile DBFs, such as trichloramine, dichloromethylamine, and dichloroacetonitrile, have also been measured in pool waters using membrane introduction mass spectrometry (MIMS) [133]. Brominated DBFs from sunscreens have been reported [136], as have DBFs from the reaction of chlorine with parabens used in lotions, cosmetics, and sunscreens [117]. 

Die Reaktion von Trichloramin mit tert.-Alkyl-chloriden in Dichlormethan in Gegenwart von Aluminiumchlorid fuhrt in einigen Fallen zur Bildung der entsprechenden tert.-Alkyl-amine in hohen Ausbeuten1. 

Tricarbonyl[( 1,2,3,4,5-r))-1 -methyl- 177-pyrrole]chromium, see Tricarbonyl( 1 -methylpyrrole)chromium(O), 2926b Trichloramine, see Nitrogen trichloride, 4137 Trichloroacetaldehyde oxime, 0694 Trichloroacetic acid, 0654 Trichloroacetonitrile, 0604 Trichloroacetyl chloride, 0607b... 

Additional nitrogen sources have been reported in the synthesis of metal nitrides. These include trichloramine, hydrazine, and N,/V-diphenylhydrazine (Table 5.4). Based on the details provided it is not clear how these may be categorized within the organizational classification discussed above... 

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