DE959096C - Process for the preparation of reaction products of chlorotriazines - Google Patents

Description

It is known to implement cyanuric chloride with organic compounds, e.g. B. with alcohols, Thio compounds, amino compounds, etc., where it has been shown that an addition via Heteroatoms, such as oxygen, nitrogen, sulfur, are made relatively easily with replacement of chlorine. On the other hand, it is much more difficult to obtain conversion products with a Carbon-carbon bond on the triazine ring.

It has been shown, for example, that aluminum chloride can be used as a catalyst Products cannot reach (K las on, Journ.

Prakt. Chem., [2], 35 [1887], p. 83), so that one was forced to take the relatively expensive route using Grignard compounds to be taken, but the yields are by no means satisfactory in all cases.

It is also known to polymerize benzonitrile or acetonitrile in the presence of alcohol at temperatures of 50 to 250 ^° and pressures of over 1000 atm., Ζ. "B. of 7000 atm Treat homologues with chlorosulfonic acid or with gaseous hydrogen halide in the presence of sulfur trioxide.

It has now been found, surprisingly, that reaction products can be obtained in a simple manner can reach the substituents bound to the triazine ring by means of a C-C bond contain, if chlorotriazines, preferably cyanuric chloride, with benzene, its homologues or its substitution products, which do not contain any unstable Η atoms. It has it has been shown that to carry out the implementation to the presence of Friedel-Crafts catalysts, in particular aluminum chloride, required in amounts of about ι to 3 moles per mole of chlorotriazine is. Furthermore, it has been shown that, in contrast to the information in US Pat. No. 1,734,029, only then good yields were obtained and the reaction can be carried out properly, if one works in the presence of such amounts of hydrogen halide that the reaction mixture is saturated with these.

For example, the chlorotriazine, preferably cyanuric chloride, with benzene in the presence of Brought aluminum chloride and hydrogen chloride to react. It turned out that at this reaction receives tri-phenyltriazine in excellent yield. Here one uses expediently excess amounts of benzene, which also act as a solvent for cyanuric chloride or for the complex formed from cyanuric chloride, hydrogen chloride and aluminum chloride to serve. In a manner similar to that with benzene, the reaction can also take place in various ways with others substituted benzene hydrocarbons are carried out, the substituents being alkyl groups, Halogen, diethylamine, etc. can be, however, due to the absence of mobile Pay attention to hydrogen atoms. Strongly acidic groups, such as B. nitro groups. The reaction of cyanuric chloride with benzene or its derivatives can be carried out with appropriate The reaction conditions are very stormy. This is e.g. B. the case when using cyanuric chloride, Aluminum chloride (in an amount of 2 to 3 mol to ι mol of cyanuric chloride) and the hydrocarbon Submitted at room temperature and with cooling with running tap water hydrogen chloride initiates; a great deal of hydrogen chloride is absorbed in the process and the temperature rises first only slightly, but after saturation with hydrogen chloride within a few seconds up to boiling point.

A moderation of this course of the reaction can be achieved by starting with the initiation of hydrogen chloride only begins after the batch has been heated to the boil, and only a moderate amount Introduces stream of hydrogen chloride. After all, this working method is also after saturation has been reached associated with hydrogen chloride with a relatively rapid release of the heat of reaction.

The reaction can be easily controlled by the gradual addition of aluminum chloride or aluminum chloride Cyanuric chloride with simultaneous supersaturation with hydrogen chloride. Since the aluminum chloride in If the benzene hydrocarbons in question are not soluble, it will be in solid form admitted. The addition can take place either at low temperature (room temperature) or at the boiling point the benzene hydrocarbons. The addition at low temperature is technical preferable, as there is no nuisance from the evaporating aromatic component when entering of solid aluminum chloride occur. When adding the cyanuric chloride one has the advantage that you can add the same dissolved in the benzene hydrocarbons, but depending on the solubility the disadvantage of a possibly increased need for these. After completing the registration the reaction is brought to an end at an elevated temperature.

The process according to the invention is explained in more detail in the following examples.

example 1

Production of triphenyltriazine from cyanuric chloride and benzene

450 g of cyanuric chloride and 1,800 ecm of benzene were placed in a 4-liter 3-tube flask with thermometer, gas inlet tube and stirrer attachment with reflux condenser and, while cooling in a water bath from 15 to 16 °, hydrogen chloride was introduced to saturation and 750 g in about 2½ hours added anhydrous aluminum chloride in small portions, continuously a little more hydrogen chloride was introduced than the reaction mixture. The internal temperature did not rise while maintaining the bath temperature 15-16 ° over 24 ^0th After all the aluminum chloride had been added, the mixture was stirred for a further 2 hours at room temperature, then heated to the boil and kept at this temperature for 2 hours. The end of the reaction could be recognized by the rather sudden solidification of the whole batch.

HCl gas had to be introduced until about half of the aluminum chloride had been introduced (114 g HCl gas); from this point on, hydrogen chloride was released from the batch, namely in an amount of 172 g until the end of the experiment. For workup, the fairly uniform appearing solid which a spatula was easy to divide to a moist powder with n ₀ was decomposed with hydrochloric acid. For this purpose it was ^{boiled six times with a} / t to 1 liter of 10% hydrochloric acid and sucked off while hot. It was then washed acid-free by boiling three to four times with ³ A to 1 liter of water and suction filtering. During this boiling process with hydrochloric acid and water, the excess benzene was also driven off completely. The residue was dried overnight in a drying cabinet 130-140 ^0th Obtained: 712 g (94.5% of theory) triphenyltriazine, melting point 230 ° to 231 °, slightly cream-colored. This crude product was already very pure, as was shown by the elemental analysis. By recrystallizing from 15V2 times the amount of xylene with the addition of a little activated charcoal by boiling for 5 minutes

triphenyltriazine could be obtained in snow-white, shiny, needle-shaped crystals F. 232 to 233 ⁰ .

Example 2

Manufacture of triphenyltriazine from
Cyanuric chloride and benzene

In a 2 liter 3 tube flask with thermometer, gas inlet tube and stirrer attachment The reflux condenser was 125 g of anhydrous aluminum chloride and 250 ecm of benzene, heated in an oil bath at 80 °, saturated with hydrogen chloride and with vigorous stirring a solution of 75 g of cyanuric chloride in 600 ecm of benzene in about 2 hours added dropwise with the simultaneous introduction of a little more HCl gas than absorbed in each case and after completing the entry a further 2 hours at the same temperature carried out.

The reaction product consisted of two liquid layers, an upper, thin, light red-brown layer (610 ecm) and a lower thick, dark layer. Apart from benzene, the upper layer contained only a small amount after stripping of the benzene remaining residue. The lower layer was made up of the complex Triphenyltriazine, aluminum chloride and hydrogen chloride, which still dissolved excess benzene contained.

Working up is effected by decomposing the complex layer with hydrochloric acid in a similar manner as in Example 1. Obtained: 116,2g (93.8% of theory) of triphenyl, F. 228 to 231 ^0, from yellow to light brown color.

Example 3

Manufacture of tri- (chlorophenyl) -triazine from cyanuric chloride and chlorobenzene

150 g of cyanuric chloride, 350 g of anhydrous aluminum chloride and 1000 ecm of chlorobenzene were placed in a 2-liter 3-tube flask with a thermometer, gas inlet tube and stirrer attachment with reflux condenser, and hydrogen chloride gas was introduced to saturation with cooling in a water bath from 18 to 22 ⁰ , whereby the internal temperature rose to 30 ⁰ . In 1 hour the bath at 90 ⁰ and in a further hour at 115 was heated to 120 ° and held for 4 hours under vigorous stirring thereby. A dark brown, apparently homogeneous solution which was still thin at 90 to 100 ° was obtained. For working up the reaction product in water of 50 liters 2V2 ⁰ was poured with stirring while the water was heated to 90 ^0th A light, still fairly soft mass was deposited. The water was poured off and the residue was kneaded several times with up to 1 liter of petroleum ether to remove the chlorobenzene it contained. In addition to the chlorobenzene, by-products formed during the reaction, namely partial substitution products of the cyanuric chloride with chlorobenzene, went into solution. The residue, which had now become powdery, was treated a few times with 2V2 liters of warm water with the addition of 50 ecm of concentrated hydrochloric acid and finally washed acid-free with water. Obtained: 265 g (78 ^fl / oi of theory) of crude product which mainly ^{melts at 285 to 286 0} except for a remainder which only melts ^{at 312 0.} This crude product consisted of tri- (chlorophenyl) triazine, namely a mixture of the o- and p-chlorine compounds and a small amount of partial substitution products of cyanuric chloride with chlorobenzene.

To isolate the two isomers, 100 g of crude product were boiled with 500 ecm of tetrahydrofuran for 1 hour with stirring, suction filtered while hot, and washed six times with 75 ecm of tetrahydrofuran each time. The residue was dried at 120 ⁰ and yielded 58.5 g of p-Trichlorphenyltriazin, F. 321 to 324 ^0, white with a yellow cast. The elementary analysis showed values consistent with theory. A precipitate crystallized from the filtrate on cooling from the suction, washed with tetrahydrofuran, and in the above manner was dried: 10 g o-Trichlorphenyltriazin, F. 202-203 ^0, white with a yellow cast. From the filtrate, the tetrahydrofuran was removed and the residue was boiled for 3 times with 500 cc of methanol, suction filtered hot and the residue washed four times with 30 cc of methanol and dried at 120 ^0: 26.6 g of o-Trichlorphenyltriazin, F. 201-202 ^0, white with a yellow tinge. A sample of this product was recrystallized from benzene, the melting point remained almost unchanged, mp 201.5 to 202 °; the elemental analysis showed values consistent with the theory.

Example 4

Production of tritolyltriazine from cyanuric chloride and toluene at low temperature

In a 1-liter flask 102 g of anhydrous aluminum chloride and 250 cc of toluene are introduced and saturated at 14 ⁰ with hydrogen chloride gas. Then, while maintaining an internal temperature of 14 to 16 ° ^C., a solution of 61 g of cyanuric chloride in 500 ecm of toluene is added dropwise over the course of 2 hours with stirring, while hydrogen chloride gas is introduced at the same time. After the end of the dropwise addition, the mixture is stirred at room temperature, the entire batch solidifying after 1 hour. It is now heated to the boil and refluxed for 5 hours.

For working up, the toluene is distilled off in vacuo, the residue boiled out four times washed with 1 liter io ° / »hydrochloric acid, washed neutral with water and dried overnight in a drying shaft at 130 ^0th Obtained: 116 g (100% of theory) tri-o- and p-tolyltriazine, light brown powder, mp 243 to 263 ⁰ . To separate off most of the p-compound, it is washed twice with 250 ecm toluene and covered with 250 ecm petroleum ether.

The residue is dried in a drying oven of 130 ⁰ overnight to yield 88.5 g (76% of theory) of tri-p-tolyltriazin with only small amounts of tri-o-tolyltriazin,

F. can be 265-268 °, obtain the pure compound with p F. 277-278 ⁰ wherefrom by recrystallization from the iSfachen amount by weight of toluene.

Filtrate and Waschtoluol are evaporated in vacuo to dryness to give 27.5 g (24% of theory) of a mixture of tri-o- and p-tolyltriazin, F. 127-182 ⁰ remains behind., Whose elemental composition corresponds exactly to the Tritolyltriazin.

Example 5

Production of tritolyltriazine from cyanuric chloride and toluene at high temperature

In an analogous manner as in Example 4, the same amounts of the reaction components with the only difference that the dropping of the toluene solution of cyanuric chloride is carried out at an internal temperature of 100 'to 104 ^0th The work-up is carried out in a manner analogous to that in Example 4, but results in a much lower yield of p-compound, a completely different ratio of o- to p-compound and resinified products.

The crude product obtained is mg (97% of theory), consisting of tri-o- and -p-tolyltriazine and still resinous with low chlorine content Products. The crude product is dark brown and somewhat sticky, so no melting point could be determined. The separation of the p-compound cannot be carried out in the same way are as in Example 4, because the crude product in toluene is already at room temperature is readily soluble. However, the separation works in the following way:

50 g of crude product are 1 hour with 500 ecm Alcohol boiled on the reflux condenser with stirring, most of which goes into solution and hot filtered;

Residue dried briefly at iio °, with 200 ecm of alcohol stirred for 1 hour at room temperature, suctioned off and in the drying cabinet of iio ° dried;

7.5 g (14.3% of theory) tri-p-tolyltriazine with small proportions of tri-o-tolyltriazine, mp 242 to 263 ⁰ , white product with a brownish sheen.

When standing, a brownish-yellow substance crystallizes out of the alcoholic filtrate, which in the Vacuum is dried at 6o °.

7.5 g (14.3% of theory) of tri-o-tolyltriazin with small amounts of tri-p-tolyltriazin, F. 132 to 138 ^0th

Although in the approach according to Example 1 the Amount of benzene is insufficient to dissolve the cyanuric chloride and aluminum chloride Even in benzene it is only very slightly soluble, occurs soon after the introduction of aluminum chloride complete dissolution of all components (already at room temperature); this solution remains relatively thin and easy to move until almost the end of the reaction. First completely against At the end of the reaction, the entire reaction mixture suddenly solidifies into a single solid Mass a. In contrast, in Example 2, there is also no one at the end of the reaction Solidification, but two layers that are liquid in the heat are obtained.

To start the reaction, a relatively large amount of hydrogen chloride is required, in Example 1 about 1.3 mol of hydrogen chloride to ι mol of cyanuric chloride. After about half of the aluminum chloride has been introduced, however, the reaction itself leads to the elimination of hydrogen chloride, namely in Example 1 about 2 moles of hydrogen chloride per mole of cyanuric chloride were available by the end of the reaction. The remaining hydrogen chloride is partly bound in the resulting complex and partly dissolved in it. The hydrogen chloride also plays a decisive role in the purity of the product obtained. It is advantageous to always maintain an excess of hydrogen chloride during the entire reaction. If this is temporarily not the case, e.g. B. with a stream of hydrogen chloride that is insufficient to immediately convert the supplied amount of aluminum chloride into the complex H (Al Cl ₄ ), so that free AlCl ₃ is present, this can be the cause of the formation of a pink triphenyltriazine.

All reactions according to the above procedure require a relatively large amount of aluminum chloride in relation to cyanuric chloride. When reacted with benzene z. B. has a The amount of 2.3 moles of aluminum chloride to 1 mole of cyanuric chloride is optimal in terms of yield and purity of the product proven. If the amount of aluminum chloride is increased above this proportion in addition, no further increase in the yield is possible if the amount of aluminum chloride is reduced however, the yield is lowered and, besides the tri-substituted ones, are formed Derivatives also include di- and monosubstituted derivatives with the replacement of 2 or 1 chlorine atom in the Cyanuric chloride. This enables the process to be tailored to the desired end product to lead accordingly.

Alkyl derivatives of benzene react just as easily as benzene itself, whereby with derivatives with longer alkyl residues, however, should be expected to result in isomerization of the alkyl group during the reaction is. With substituted benzene hydrocarbons, e.g. B. chlorobenzene (Example 3), the course of the reaction is no longer so stormy, so that all Components can bring together immediately, without a sudden increase in temperature when introducing to have to fear of hydrogen chloride.

The reaction also succeeds with dimethylaniline, only the reaction is due to the basic one Character associated with the addition of the amine with a considerable heat release, so that the Amine must be introduced very slowly with ice cooling.

According to the invention, chlorotriazines other than chlorotriazines can of course in a similar manner Find cyanuric chloride use, which on the triazine

ring in addition to ι or 2 chlorine atoms or two or one other substituent, such as alkyl, alkoxy, Dimethylamino groups, etc., carry.

The reaction products obtained by the process of the invention are versatile Usable, e.g. as intermediates for nouns, dyes, etc.

Claims (2)

PATENT CLAIMS: i. Process for the production of reaction products of chlorotriazines, preferably cyanuric chloride, with aromatic hydrocarbons or their substitution products with the formation of carbon-carbon bonds amTriazine ring, characterized in that the chlorotriazines with benzene, its homologues or its substitution products, which contain no labile H atoms, in the presence of about ι to 3 mol Friedel-Crafts catalysts, especially aluminum chloride, and in the presence of such amounts of hydrogen halide that the reaction mixture is saturated with these, reacted will. 2. The method according to claim 1, characterized in that that the catalyst or the chlorotriazine is gradually introduced into the reaction mixture. Considered publications: German Patent No. 549,969;
. U.S. Patent Nos. 1,734,029, 2,503,999, 598,811; Journ. Prakt. Chem. [2], 35 [1887], p. 83; Ber. German chem. Ges., 33 [1900], pp. 1053, 1054; C. A. Thomas, Anhydrous Aluminum Chloride in organic chemistry, New York 1941, p. 151. © 609 808 2.57