Triazine water

Potentially explosive reaction with nitric acid + sulfuric acid, bromine trifluoride, nitrosyl chloride + platinum, nitrosyl perchlorate, chromyl chloride, thiotrithiazyl perchlorate, and (2,4,6-trichloro-l, 3,5-triazine + water). Reacts to form explosive peroxide products with 2-methyl-1,3-butadiene, hydrogen peroxide, and peroxomonosulfuric acid. Ignites on contact with activated carbon, chromium trioxide, dioxygen difluoride + carbon dioxide, and potassium-tert-butoxide. Reacts violendy with bromoform, chloroform + alkalies, bromine, and sulfur dichloride. 

Melamine. Melamine (cyanurotriamide, 2,4,6-ttiainino-j -triazine) C H N, is a white crystalline soHd, melting at approximately 350°C with vaporization, only slightly soluble in water. The commercial product, recrystallized grade, is at least 99% pure. Melamine was synthesized eady in the development of organic chemistry, but it remained of theoretical interest until it was found to be a usehil constituent of amino resins. Melamine was first made commercially from dicyandiamide [461-58-5] (see Cyanamides), but is now made from urea, a much cheaper starting material (9—12) (see also... 

Other amino resins besides MF resins are used to a lesser degree in coatings. Urea—formaldehyde resins are used in some coatings for wood furniture because these resins cross-link at lower temperatures than MF resins and the higher water resistance and exterior durabiUty that can be obtained using MF resins are not needed. Ethers of formaldehyde derivatives of 6-phenyl-l,3,5-triazine-2,4-diamine [91-76-9] (benzoguanamine resins) give... 

Several triazinyl ketones isomerize to 4-acetamidopyrimidines. TTiis is seen in the C-acylation of 2,4,6-trimethyl-l,3,5-triazine (708) with benzoyl chloride in the presence of sodium amide to give the ketone (709) which undergoes a Dimroth-like rearrangement in boiling water to afford A-(2-methyl-6-phenylpyrimidin-4-yl)acetamide (710) it can be seen that the acylating agent determines the identity of the 6-substituent 64JHC145). 

This paper deseribes a rapid and versatile on-line-SPE LC-MS/MS method developed for the determination of various pestieides and tlieir metabolites in water. 28 pestieides, ineluding various triazines, phenylureas, organophosphorous eompounds and other speeies, were seleeted for systematie investigations. 

Melamine (2,4,6-triamino-l,3,5-triazine) [108-78-1] M 126.1, m 353", pK 5.00. Crystd from water or dilute aqueous NaOH. 

The drinking water maximum contaminant level (MCL) set by the USEPA for altrazine is 0.003 mg/L and its Reference Dose (RfD) is 3.5 ingAcg-d. How many liters of water containing atrazine at its MCL would a person have to drink each day to e.xceed the RfD for this triazine herbicide ... 

Hydrolytic cleavage of the methylmercapto group usually proceeds very readily and in practically quantitative yield even on short boiling in water acidified with a few drops of hydrochloric acid. The readiness of the hydrolysis can be affected very substantially by substitution as shown in the case of 4-methyl-3-methylmercapto-5-thioxo-4,5-dihydro-l,2,4-triazine which was hydrolyzed only with ZN hydrochloric acid. "... 

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). 

The catalytic effect of protons has been noted on many occasions (cf. Section II,D,2,c) and autocatalysis frequently occurs when the nucleophile is not a strong base. Acid catalysis of reactions with water, alcohols, mercaptans, amines, or halide ions has been observed for halogeno derivatives of pyridine, pyrimidine (92), s-triazine (93), quinoline, and phthalazine as well as for many other ring systems and leaving groups. An interesting displacement is that of a 4-oxo group in the reaction of quinolines with thiophenols, which is made possible by the acid catalysis. 

Chloro-5,6-diphenyl-as-triazine readily undergoes methoxy-de-chlorination at 25° (< 12 hr) with methanolic methoxide and at 65° (4.5 hr) in non-basified methanol. The chloro group is also displaced by hydrazine (80°, 1 hr), ammonia (140°, 6 hr), and phenyl-magnesium bromide (70°, 12 hr), the latter forming the triphenyl compound 315.3-Chloro-6-phenyl-as-triazine is unstable to cold water or alkali and to hot alcohol or aqueous potassium carbonate. ... 

Dichloro-s-triazine and its 6-alkyl analogs are as easily hydrolyzed by water as trichloro-s-triazine and, on suspension in aqueous ammonia (25°, 16 hr), the first is diaminated in good yield. 2,4-Bistrichloromethyl-6-methyl- and -6-phenyl-s-triazines (321) require a special procedure for mono-alkoxylation (0-20°, 16 hr, alcoholic triethylamine) disubstitution occurs at reflux temperature (8 hr). Aqueous triethylamine (100°, 3 hr) causes complete hydroxy-lation of 2,4,6-tris-trichloromethyl-s-triazine which can be mono-substituted with ammonia, methylamine, or phenoxide ion at 20°. 

Tricyano-s-triazine (322) is mono-substituted very rapidly with anhydrous methanol (20°, few min) and with water di- and trisubstitution products also result under mild conditions (65°, one min, and 65°, several hr, respectively, for methanol). 

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 ... 

It was found that 1,2,4-triazine 4-oxides 55 are active enough to react with cyanamide under basic conditions according to the deoxygenative mechanism to form 5-cyanamino-l,2,4-triazines 73 (00TZV1128). This reaction seems to be facilitated by the easy aromatization of cr -adducts by the Elcb elimination of water. 

Deoxygenative autoaromatization was reported to occur in the reaction of 3-amino-1,2,4-triazine 2-oxides 42 with alcohols in the presence of HCl or acetyl chloride. In this case the intermediate cr -adducts undergo elimination of water or acetic acid, resulting in 6-alkoxy-3-amino-l,2,4-triazines 75 (77JOC3498). 1,2,4-Triazine 1-oxides do not react with alcohols under these conditions (77JOC3498). 

The reaction of 1,2,4-triazine 4-oxides 55 with water in the presence of benzoyl chloride affords 3-hydroxy-1,2,4-triazines 78. The mechanism suggested for this reaction includes acylation of the substrate at the oxygen of the iV-oxide group, followed by the addition of water to the 1,2,4-tiiazinium cation and the autoaromatization of the (T -adducts with the elimination of benzoic acid. 

V. Pichon, F. Chen, M.-C. Hennion, R. Daniel, A. Martel, F. Fe Goffic, J. Abian and D. Barcelo, Preparation and evaluation of immunosoi bents foi selective rtace enrichment of phenylurea and triazine herbicides in environmental waters . Anal. Chem. 67 2451-2460(1995). 

Figure 13.10 LC-LC chromatogram of a surface water sample spiked at 2 p.g 1 with ati azine, and its metabolites (registered at 220 nm). Conditions volume of sample injected, 2 ml clean-up time, 2.60 min ti ansfer time, 4.2 min The blank was subtracted. Peak identification is as follows 1, DIA 2, HA 3, DEA 4, atrazine. Reprinted from Journal of Chromatography, A 778, F. Hernandez et al, New method for the rapid detemiination of triazine herbicides and some of thek main metabolites in water by using coupled-column liquid cliromatography and large volume injection , pp. 171-181, copyright 1997, with permission from Elsevier Science.

Figure 13.20 GC-FID chromatograms of an exuact obtained by (a) SPE and, (b) lASPE of 10 ml of municipal waste water, spiked with 1 p.g 1 of seven s-triazines (c) represents a blank mn from lASPE-GC-NPD of 10 ml of EIPLC water. Peak identification is as follows 1, ati azine 2, terbuthylazine 3, sebuthylazine 4, simetiyn 5, prometiyn 6, terbutiyn 7, dipropetiyn. Reprinted from Journal of Chromatography, A 830, J. Dalliige et al, On-line coupling of immunoaffinity-based solid-phase exUaction and gas chi-omatography for the determination of 5-triazines in aqueous samples , pp. 377-386, copyright 1999, with permission from Elsevier Science.

P. Hernandez, C. Hidalgo, J. V. Sancho and P. J. Lopez, New method for the rapid determination of triazine herbicides and some of their main metabolites in water by using coupled-column liquid cliromatography and large volume injection , 7. Chromatogr. 171-181 (1997). 

Y. Pico, A. J. H. Eouter, J. J. Vreuls and U. A. Th Brinkman, On-line tr-ace-level enrichment gas cliromatography of triazine herbicides, organophosphoms pesticides and organosulfur compounds from drinking and surface waters . Analyst 119 2025-2031 (1994). 

---