1.3.5- Triazine, tris-trichloromethyl

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°. 

Trihalomethyl groups can be replaced in nucleophilic substitution reactions in sufficiently activated systems, as for example in. v-triazines. 2,4,6-Tris(trichloromethyl)-.v-triazine is converted into 2,4,6-triamino-.v-triazine by ammonia. 

Complete Replacement of CCI3 by NH2. 2,4,6-Tris-(trichloromethyl)-s-TRiAZiNE (Xll). A solution containing 8.7 grams of XII (0.02 mole) in 25 ml. of DMF was maintained for 4 hours at a temperature of 165° C., during which time a dry stream of ammonia was introduced. Upon cooling, a tan solid precipitated which was filtered under vacuum and dried. It could be recrystallized from water and proved to be identical in every respect, with melamine (XV, R = H) (17). Conclusive proof was obtained by mixed melting point of the picrate (21). The amount of 1.2 grams of XV (R = H) corresponds to a yield of 48%. 

The preparation of 2,4,6-tris(trichloromethyl)-l,3,5-triazine (4) can also start from acetonitrile by direct chlorination and trimerization without isolation of the intermediate trichloroacetonitrile.154... 

Halogenated Ketones and Trichloromethyl Triazines It is known that halogenated ketones liberate a Cl radical upon light exposure [45]. Substituted tris-(trichloromethyl)-l,3,5-triazines (10.25) generate a chlorine radical and a carbon-centered radical through the cleavage of a C-Cl bond [46,47] their absorption maxima are located around 400 nm. 

Examples of additives are the following EA = iodonium salt, e.g. diphenyliodonium hexafluorophosphate (more rarely, a sulfonium salt) and related derivatives [113], alkyl halide, e.g. phenacyl bromide [1.14] and triazine, e.g. 2,4,6-tris(trichloromethyl)-l,3,5-triazine ED = borate disulfide, group IVb dimetal [1.15] HD = alcohol, THE, thiol, benzoxazine, aldehyde, acetal, silane (e.g. tris(trime1hylsilyl)silane = (TMS)3Si-H) [1.16]), germane, borane, stannane, alkoxyamine, silyloxyamine, polymer substrate, etc. EPD = amine [1.17], thiol, etc. The generated radicals (e.g. Ph, R, RsSi, RR C R R in [1.13]-[1.17] ) are the initiating species. Efficient novel or newly modified dye structures in the Dye/amine, Dye/iodonium salt or Dye/silane two-component PISs have been proposed within the last 4 years (see section 1.3.5). 

Tris(trichloromethyl)-l,3,5-triazine 86 was transformed to trifluorometh-ylderivative 74 under the action of SbFg (Scheme 37) [62],... 

In theory, the cotrimerization of two or three nitriles should give mixtures of four or ten 1,3,5-triazines respectively however, reactions may be carried out selectively if two nitriles of different reactivities are used. Thus the reaction between two equivalents of tri-chloromethyl cyanide and one equivalent of acetonitrile gives just one product (74JOC2591). Trichloromethyl cyanide readily forms the adduct (156), whilst acetonitrile does not, hence the selectivity is ensured (Scheme 94). Clearly, this route can only be applied to the synthesis... 

Trichloroisocyanuric acid , see l,3,5-Trichloro-l,3,5-triazinetrione, 1036 Trichloromelamine, see 2,4,6-Tris(chloroamino)-l,3,5-triazine, 1092 Trichloromethane, see Chloroform, 0371 Trichloromethyl perchlorate, 0333 Trichloromethyl peroxyacetate, 1094 5-Trichloromethyltetrazole, 0653 5 -Trichloromethyl-1 -trimethylsilyltetrazole, 1921 Trichloroperoxyacetic acid, 0655... 

The trichloromethyl group in s-triazines is sufficiently reactive to he displaced by ammonia, amines, or alkoxides even if two deactivating groups have already been introduced. In contrast, under much more vigorous conditions benzotrichloride and 2,6-bis(trichloro-methyl)pyridine are unreactive towards ammonia in dimethyl-formamide (2 hr, 165°). Tris-amination of 2,4,6-tris-(trichloro-methyl)-s-triazine is complete in aprotic, but not in protic, solvents. 

Like nitrile groups, trichloromethyl groups as in tris(trichlo-romethyl)-5-triazine (279) can be replaced stepwise by N-(2-hydroxyethyl)-piperazine to 280 and subsequently by ethylamine to 281 (67GEP1670564 85KGS1557). For the analogous conversion of 2-triduoroquinoline by sodium amide to 2-aminoquinoline see Kobayashi e/ al. (75CPB2044). 

Reactions of replacement of SMe [79], trichloromethyl [97] or trifluoromethyl groups represent effective approaches for modifications of trifluoromethyl containing 1,3,5-triazines. Direct vapor-phase fluorination of tris-(trifluoromethyl)-s-triazine 74 has been studied and was found that the perfluoroalkyl groups of 74 were progressively replaced by fluorine to give mixture of 2,4-difluoro-6-trifluoromethyl-s-triazine 156 and 2,4-bis-(trifluoromethyl)-6-fluoro-s-triazine 157 (Scheme 66) [98]. Photoirradiation of tris-(trifluoromethyl)-i-triazine in cyclohexane leads to a mixture of adduct 158 and dihydrocompound 159 (Scheme 66) [99]. 

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