Chlorides cyanuric

The commonest reactions are those involving nucleophilic attack by substituted primary amines. The first Cl atom is easily replaced in the presence of alkali at room temperature, the second Cl atom requires more forcing conditions, which vary with the basicity of H2NR, but in general a temperature of 55-60 °C suffices. A temperature of 90-100 °C is required for the third chlorine atom, higher temperatures still in the case of weakly basic 

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Cyanogen chloride, CICN. Colourless liquid, m.p. — C,b.p. 13 C(aqueousCN plusCl2). Linear molecule, polymerizes to cyanuric chloride (CICN),. Extremely poisonous. 

Since the exocyclic sulfur is more reactive in the ambident anion than in A-4-thiazoIine-2-thione. greater nucleophilic reactivity is to be expected. Thus a large variety of thioethers were prepared in good yields starting from alkylhalides (e.g.. Scheme 38 (54, 91, 111, 166-179). lactones (54, 160), aryl halides (54, 152. 180, 181), acyl chlorides (54. 149, 182-184). halothiazoles (54, 185-190), a-haloesters (149. 152. 177. 191-194), cyanuric chloride (151). fV.N-dimethylthiocarbamoyl chloride (151, 152. 195. 196), /3-chloroethyl ester of acrylic acid (197), (3-dimethylaminoethyl chloride (152). l,4-dichloro-2-butyne (152), 1,4-dichloro-2-butene (152), and 2-chloro-propionitrile (152). A general... 

Stilbene Derivatives. Most commercial brighteneis aie bistria2inyl derivatives (1) of 4,4 -diarmnostilbene-2,2 -disulfonic acid (Table 1). The usual compounds are symmetric preparation begias with reaction of 2 moles of cyanuric chloride derivatives with 1 mole of... 

Several studies on FWAs have concluded that diarninostilbenedisulfonic acid/cyanuric chloride (DAS/CC) and distyrylbiphenyl (DSBP) type whiteners are of a low order of toxicity. Thek safety has been extensively reviewed by governmental agencies there is no evidence of human health ha2ards. FWA producers and users consider these products to be both safe and beneficial to the ultimate consumer. This view is supported by appropriate trade associations. A comprehensive review of available safety and environmental data has been pubflshed (82). In addition, principal suppHers are conducting life cycle analyses on the primary whiteners in use (ca 1993). 

Cyanuric fluoride is readily hydrolyzed to 2,4,6-thhydroxy-l,3,5-triaziae [108-80-5] (cyanuric acid). Cyanuric fluoride reacts faster with nucleophilic agents such as ammonia and amines than cyanuric chloride. 

Miscellaneous Disazo Dyes. Another group of disazo dyes is prepared by condensation of two identical or different aminoazo compounds commonly with phosgene, cyanuric chloride, or fumaryl dichloride, the fragments of which act as blocking groups between chromophores. 

Organic Derivatives. Although numerous mono-, di-, and trisubstituted organic derivatives of cyanuric and isocyanuric acids appear in the hterature, many are not accessible via cyanuric acid. Cyanuric chloride 2,4,6-trichloro-j -triazine [108-77-0], is generally employed as the intermediate to most cyanurates. Trisubstituted isocyanurates can also be produced by trimerization of either aUphatic or aromatic isocyanates with appropriate catalysts (46) (see Isocyanates, organic). Alkylation of CA generally produces trisubstituted isocyanurates even when a deUberate attempt is made to produce mono- or disubstituted derivatives. There are exceptions, as in the production of mono-2-aminoethyl isocyanurate [18503-66-7] in nearly quantitative yield by reaction of CA and azitidine in DMF (47). 

Conversion of CA into cyanuric chloride [108-77-0] (C1CN)3 by PCl is another example of reaction at carbon (78). Cyanuric chloride as an imidoyl chloride reacts as an acid chloride, unlike chloroisocyanurates. 

Cyanuiic chloiide reacts with sodium sulfide to form tritliio(iso)cyanuric acid [638-16 ] (11). For a review of cyanuric chloride chemistry, see Reference 79. 

A convenient laboratory synthesis of high purity CA is hydrolysis of cyanuric chloride (7). On a commercial scale, CA is produced by pyrolysis of urea [57-13-6]. When urea is heated at - 250 ° C for about an hour, it is converted to crude CA with evolution of ammonia. 

On the large scale, cyanuric chloride is produced by the trimerization of cyanogen chloride. The cyanogen chloride is produced by chlorination of hydrogen cyanide and is trimerized by passing it over charcoal impregnated with an alkaline-earth metal chloride at a high temperature (250—480°C). 

Cyanuric chloride (TCT, 2,4,6-trichloro-l,3,5-triazine) [108-77-0] M 184.4, m 146-149 , 154 , h 190 . Crystd from CCI4 or pet ether (b 90-100°), and dried under vacuum. Recrystd twice from anhydrous benzene immediately before use [Abuchowski et al.J Biol Chem 252 3582 1977]. 

This monomer is prepared by reacting cyanuric chloride with excess allyl alcohol in the presence of sodium hydroxide at 15-20°C. Laminates based on polyester resins containing triallyl cyanurate are claimed to be able to withstand a temperaure of 250°C for short periods. 

Respiratory sensitizers Isocyanates proteolytic enzymes p-phenylene diamine complex salts of platinum cyanuric chloride. ... 

Aininopolycarboxylic acids Barium cyanide P-ainines Cyanuric chloride Diaininoinaleonitrile Lactic acid Methionine Sodium cyanide... 

Flament et al made use of the partial replacement of two chlorine atoms in cyanuric chloride (12) with methoxyl groups, the 2,4-di-methoxy-6-chloro-l,3,5-triazine (13) formed was dehalogenated to 2,4-dimethoxy-1,3,5-triazine (14) and this yielded the product (2) on gentle hydrolysis. 

Goi. As noted previously, an a-chlorine atom renders a ring-nitrogen atom very weakly basic. Cyanuric chloride (5) is a very weak base both because s-triazines are of low basicity and because each of the ring-nitrogen atoms is alpha to two chlorine atoms. Hence, this compound should be insensitive to acid catalysis or acid autocatalysis and this has been observed for the displacement of the first chlorine atom with alcohols in alcohol-acetone solution and with water (see, however. Section II,D,2,6). 

Compounds of type 6 containing ZR substituents with a -electron pair on the Z atom bound to the ring carbon (Z = O, S, NH) are formed by displacement of the first chlorine atom of cyanuric chloride by weU-known nucleophiles. Their basicity should be greater than that of cyanuric chloride because of the mesomeric electron release of the ZR... 

The reactivity of cyanuric chloride (2,4,6-trichloro-s-triazine) as an indication of s-triazine activation is misleadingly high because of mutual activation of the chlorines meta activation > ortho or para activation) and its symmetry (cf. Section III,A, 1), However, the greatest variety of nucleophilic substitutions have been investigated with this substrate. 

Even polyalkoxy-s-triazines are quite prone to nucleophilic substitution. For example, 2,4,6-trimethoxy-s-triazine (320) is rapidly hydrolyzed (20°, dilute aqueous alkali) to the anion of 4,6-dimethoxy-s-triazin-2(l )-one (331). This reaction is undoubtedly an /S jvr-4r2 reaction and not an aliphatic dealkylation. The latter type occurs with anilines at much higher temperatures (150-200°) and with chloride ion in the reaction of non-basified alcohols with cyanuric chloride at reflux temperatures. The reported dealkylation with methoxide has been shown to be hydrolysis by traces of water present. Several analogous dealkylations by alkoxide ion, reported without evidence for the formation of the dialkyl ether, are all associated with the high reactivity of the alkoxy compounds which ai e, in fact, hydrolyzed by usually tolerable traces of water. Brown ... 

Because of the high polarity of the C=N double bonds, cyanuric chloride (120, R= Cl) is comparable with a carboxylic acid chloride. This explains its smooth reaction with diazomethane to yield dichloro-(diazomcthyl)-l,3,5-triazine (121, R = The analogous com-... 

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