HU201518B - Process for producing phenyl-(di)isocyanate derivatives - Google Patents

Abstract

Aromatic isocyanates the prods. are prepd. from appropriately substd. aniline derivs. or the inorganic salts of these by batchwise, semi-continuous or continuous reaction with gaseous or liq. phosgene at 0-120 deg.C and atmospheric or elevated pressure of 0-50 bar in a multi-component medium contg. di-substd. carbamoyl-chloride or di-substd. amine or tri-substd. urea as solvent and/or catalysts.

Description

and R 2 and R 3 may be taken together with the nitrogen atom to form a hexamethyleneimino or morpholino group, and as a catalyst a (disubstituted) carbamoyl chloride of formula (II) wherein the substituents are as defined above or a trisubstituted urea of formula (III) R 4 is hydrogen or halo, C 1-4 straight or branched alkyl optionally substituted with one or more halogen atoms, R 5 and R f and C 1-4 straight or branched alkyl.

HU 201518 Β

FIELD OF THE INVENTION The present invention relates to a process for preparing phenyl (di) isocyanate derivatives of the formula (I) wherein n is 1 or 2, R and R1 are hydrogen or halogen, C1-C4 straight or branched, optionally alkyl, mono- or polysubstituted with halogen, and (C 1 -C 2) alkylaniline - or their hydrochloric acid salt with phosgene, in a solvent medium, optionally in the presence of a catalyst, by reaction with an organic solvent and / or (disubstituted) carbamoyl chloride (ka) t - wherein R 2 and R 3 are straight or branched C 1 -C 4 alkyl, C 2 -C 4 alkenyl, C 3 -C 6 cycloalkyl, singly or multiply substituted by halogen or hydroxy, or phenyl and R2 and R3 together with the nitrogen atom are hexamethylene, an imino or morpholino group, the catalyst being a (disubstituted) carbamoyl chloride of formula II, wherein the substituents are as defined above, or a trisubstituted urea of formula (ΠΙ), wherein R 4 is hydrogen or halo; straight or branched chain alkyl group optionally substituted with one or more halogen atoms. R5 and R0 are C 1 -C 4 straight or branched alkyl, the aniline-phosgene reaction is carried out at a temperature of 0 to 120 ° C, at a pressure of 0.5 bar, and the target product is recovered from the reaction mixture in a known manner.

Aromatic isocyanates are essential raw materials and intermediates in many areas of the chemical industry. Aromatic isocyanates are mainly used in the manufacture of pharmaceuticals and pesticides, while aromatic diisocyanates are mainly used in the production of polyurethane foams and elastomers.

Due to its widespread use, many processes have been developed for the production of organic isocyanates, and these processes are well documented (Houben-Weyl, Methoden d Orsanischen Chemie, Vol. 75, 1952); Chem. Rev. 72/5/457 (1972)]. Of the various processes, the production of isocyanates based on the interaction of appropriately substituted aniline and phosgene, the decomposition of carbarates and the reaction of aromatic nitro compounds with carbon monoxide is of practical importance.

Of these, the phosgenic process is the most commonly used method in industrial practice.

Isocyanate production by reaction of amines with phosgene has long been known. [Rental. 17, 1284 (1884)]. In practice, the reaction is carried out at a temperature of 130-160 ° C in an amount of 8-10 times the amount of solvent and excess phosgene relative to the amine.

It is known in the literature that aniline reacts with phosgene at high temperatures even at room temperature or below.

[Chem. Port. 73/1/75 (1973)].

[Acta. Chim. Acad. Sci. Hung. 61/2/197 (1969)].

Hydrochloric acid is formed as a by-product in this reaction. which converts the unreacted aniline into aniline hydrochloride. and this salt with phosgene is only higher. It is capable of reacting at temperatures of 100-180 ° C at an appropriate rate. The temperature depends on the substituents on the aromatic ring.

For electron-withdrawing substituents (e.g., halogens), the reaction is only satisfactory at elevated temperatures (e.g., above 160 ° C for 3,4-dichloroaniline). [Yuki Goshei Kogaku Kyokai Shy 15 140 (1957)]. By increasing the temperature, however, the amount and quality of the target product is reduced due to various side reactions (eg carbodiimide formation). Hungarian patent]. Furthermore, most importantly, the solubility of phosgene is reduced at high temperatures and thus its concentration is reduced and the reaction leading to the formation of urea is increasingly important along with the reaction of isocyanate formation. [Chem. Soc. Rev. 3, 209 (1974).]

Processes for preparing isocyanates by reacting amine hydrochloride with phosgene at low temperatures (below 100 ° C) using various catalysts are known. Such procedures are described e.g. The following patents:

US 2,733,254 Catalyst: Boron trifluoride etherate

DE 1 233 854 Catalyst: tertiary amine

GB 1 085 824 Catalyst: Tetrasubstituted Thiourea

GB 574 222 catalyst: metal (Fe, Co, Zn, etc.) chloride

GB 1 430 350 Catalyst: Dialkyl Acid Amide

Catalyst: disubstituted acid amide, tetrasubstituted urea.

A common feature of the above catalysts is that they catalyze the side reactions of the isocyanates formed, in addition to accelerating the reaction of aniline hydrochloride with phosgene, according to our laboratory measurements and chemical literature. Thus, the resulting isocyanate can be recovered from the reaction mixture with lower yields, lower drug content and low storage stability (the latter being due to dimerization and trimerization processes).

Tertiary amine, boron trifluoride, heavy metal chloride are used for dimerization and trimerization of isocyanates. [High Polimere Vol. XVI. Poliurethanes Chem and. Techn. I. Wiley Part I. (1967)], while for the polymerization of dimethylformamide [Chem. Port. Vol 72. (1972) p. 476]. In the preparation of organic isocyanates, carboxylic acid amides (e.g., dimethylformamide) are chemically reacted with isocyanates (e.g., phenyl isocyanate) [J. Org. Chem. 25, 2245 (1960)], and the by-products thus formed (e.g., N-phenyl-N, N-dimethylformamidine) reduce yields and degrade the quality of the isocyanates formed. This side reaction may initiate dimerization and trimerization processes with new isocyanates. [Chem. Port. Vol 72. No. 5. (1972) p. 478] and the resulting heterocyclic compounds cause degradation of quality and loss of storage stability.

Another problem is that amides are formed from acid amides by phosgene. [Ansew. Chem. Jahrs 72, No. 22, 1960].

And urea and thiourea produce NN-dialkyl allofamoyl chloride and / or Ν, Ν-dialkyl chloroformamidines even at low temperatures (810 ° C). in good yield (70-90 ^c h).

[J. Org. Chem., 28, 1427 (1963); Angev. Chen. 72. Jahrg. (1960) No. 22: Chem. Jahrg 97 1232, etc.].

HU 201518 Β

The disubstituted amine disclosed in HU 159 106 also acts in the same way as tetrasubstituted urea. As is well known in the literature, when phosgene is introduced in a solvent solution of amines (i.e. excess amine), a product consisting mainly of urea and amine hydrochloride is obtained. as described in U.S. Pat.

Laboratory testing of these catalysts showed that only about 70-80% yield was achieved in solvent deprotection and distillation of the aromatic isocyanates (since the catalysts all remain in the bottom product) (see Examples 17 and 18 of the present invention).

In order to overcome the above disadvantages, it is an object of the present invention to provide a process for preparing a phenyl (di) isocyanate derivative which is more economical and has a higher reaction rate compared to the disclosed processes. higher yields, high purity, selective preparation of the desired product without pyrolytic degradation of the desired product, and the reaction product can be readily recovered by commercially available methods. In our attempts to develop the present invention, it has been found that the desired phenyl (di) isocyanate derivative can be prepared readily and in high yields when the appropriately substituted aniline of formula (1) wherein n is 1 or 2, R and R 1 is hydrogen or halogen,

C 1 -C 4 linear or branched, optionally substituted singly or multiply alkyl group, (C 1 -C 2 alkyl) ananyl group, or its hydrochloric acid salt with phosgene, optionally using a catalyst,

- anil derivatives of the formula (I) wherein the substituents have the meaning given above - or their hydrochlorides in an amount of 1 to 10 times the (disubstituted) carbamoyl chloride (ka) of the formula (II) - in the formula R? and R? C 1-4 straight or branched chain alkyl, C 2-4 alkenyl, C 3-6 cycloalkyl or phenyl optionally substituted by one or more halo or hydroxy groups, and R? and R3 are dissolved together with the nitrogen atom in a solvent (mixture), either alone or in a mixture (preferably) (halogenated) -aliphatic or - aromatic hydrocarbon, preferably in the presence of a hexamethyleneimino or morpholino moiety and without the use of a separate catalyst, obsession

- the aniline derivatives of formula (I) wherein the substituents are as defined above, or their hydrochlorides are dissolved in 1-10 times the amount of the inorganic organic solvent, preferably (halogenated) aliphatic or aromatic hydrocarbon, and the catalyst is 0 relative to the aniline, 05 to 5.0% by weight of (disubstituted) carbamoyl chloride of formula II, wherein the substituents are as defined above, or 0.5 to 15% by weight of trisubstituted urea of formula III, wherein Rt is hydrogen or halogen. C 1 -C 4 straight or branched chain alkyl optionally mono- or polysubstituted by halogen. R5 and

And R 1 is in the presence of a straight or branched alkyl group containing from 1 to 4 carbon atoms.

Reaction with phosgene at a temperature of 0 to 120 ° C, at atmospheric pressure or at 0 to 5 bar, yields the phenyl (di) isocyanate derivative from the reaction mixture in a known manner, preferably after solvent removal by distillation of phosgene and hydrochloric acid by vacuum distillation. .

The reaction can be carried out batchwise, semi-continuously and continuously in the appropriate apparatus.

The (disubstituted) carbamoyl chlorides of formula (II) used as the solvent or catalyst in the reaction can be prepared by methods known in the art and can be reacted with the aniline phosgene, but it is also possible to derive the phenyl (di) isocyanate derivative. disubstituted carbamoyl chloride-containing cuvette residue or distillate. The compounds of formula (Π) can also be prepared in the phosgenation process itself. In this case, the (disubstituted) aliphatic amine is mixed with either the cyclic N-containing compound or the amine hydrochloride in the fed aniline solution and the reaction conditions are maintained (min.

2 to 3 times) excess phosgene, perfect mixing, temperature (70-100 ° C) for carbamoyl chloride formation, which ensures (disubstituted) carbamoyl chloride formation. In this case, it is absolutely necessary to avoid the possibility of using the HU 159 106. The invention provides tetrasubstituted ureas (see Example 8 of the present invention).

The solvent and optional catalyst (II) or (III) used in the aniline-phosgene reaction is determined by the chemical nature of the aniline derivative used, the availability of the catalyst, and the range of use of the isocyanate produced. For example; if N-aryl-N'N'-dimethylurea is available and the isocyanate is used to prepare this type of compound, it is preferable to use this catalyst (i.e., compounds of formula III). (Such procedures are described in Examples 12-14, 33 and 34). In this case, the reaction is carried out by dissolving the aniline derivative (I) or its hydrochloride in 5 to 10-fold amounts in an inert organic solvent, adding from 0.5 to 2.0% by weight of the trisubstituted compound (III) to the aniline urea catalyst and phosgeneation at 100-120 ° C or addition of 2-15% by weight of catalyst (III) at 50-110 ° C (increasing the amount of catalyst can reduce the temperature used) .

If the aniline derivative (I) is highly reactive, 0.05-5.0% by weight of the carbamoyl chloride derivative (II) catalyst in an inert organic solvent is useful (see Examples 19-25 and 27-32). ). In this case, two methods are used to carry out the reaction:

in one, the aniline derivative or the hydrochloride of formula (I) is dissolved in 5 to 6 times the amount of the inorganic organic solvent and added in parallel with the phosgene in a / preferably organic solvent of the former which is heated to 90-130 ° C while phosgene was introduced and 0.1-1.2% by weight relative to aniline

-4I

The amount of catalyst (II) was added and after the addition and after the reaction was complete, the target product was recovered from the reaction mixture.

in the other, the aniline derivative of the formula I or its hydrochloride is dissolved in 2 to 10 times the amount of the inert organic solvent, 0.4 to 1.1% by weight of the catalyst II is added to the aniline, followed by in parallel with the phosgene, it is introduced into an (preferably the same) ineneous organic solvent in which liquid phosgene is added at 0-5 ° C or gaseous at 20110 ° C and the aniline-phosgene reaction is carried out at 85-110 ° C .

If the aniline derivative of formula (I) has a reduced reactivity (because there are electron-withdrawing substituents on the aromatic ring, e.g., 3,4-dichloroaniline, 4-chloro-3-trifluoromethylaniline, etc., or aniline hydrochloride, the starting compound Higher concentrations of the carbamoyl chloride derivative of formula (II) provide a sufficiently rapid and selective aniline-phosgene reaction (see Examples I-III and 26).

In this case, four methods are employed depending on the chemical properties of the aniline:

dissolving the aniline hydrochloride (I) in a 1 to 10 fold amount of the compound (II) at low temperature (0-1-5 ° C) and phosgenation at 30-50 ° C (see Figure 2). , 4,

Examples 5, 7, 10)

- dissolving the aniline (hydrochloride) of the compound of formula I in 5 to 10 times the amount of the compound of formula II at low temperature (0 to 1 to 10 ° C) relative to the aniline (and in Example 8 this compound was prepared from the diethylamine and phosgene in the reaction itself) and the phosgenation was carried out at 50-80 ° C (see Examples 1, 8).

- dissolving the aniline (s) or their hydrochlorides (I) or their hydrochlorides (4) in an inert organic solvent at a temperature of 40-80 [deg.] C. in parallel with the phosgene at a concentration of 1 to 3 times the aniline It is introduced into the carbamoyl chloride derivative (II) and post-reacted until the formation of the phenyl (di) isocyanate (s) (see Examples 6, 9-26).

- dissolving the aniline derivative (1) or its hydrochloride in a 1 to 10-fold amount of a solvent mixture containing an inorganic solvent (1: 1) to 4: 1 and phosgene It is introduced into the solution at a temperature between 0 and -30 ° C, and the reaction is raised by raising the temperature to 50-70 ° C (see Figs.

Examples 3 to 11).

In conclusion, the process of the present invention has the advantage that it is independent of the chemical properties (solubility, reactivity, etc.) of the aniline of formula (I). the aniline-phosgene reaction at relatively low (0-120 ° C), without damage to the final product, high reaction rate, high conversion (yield: 95-99.3%). selective product formation (97.2-98.7 ^< 7r active ingredient content), can be accomplished.

The process of the invention is illustrated by the following examples. without limiting the patent claim to these. In the Examples, the active substance content of the phenyl (di) isocyanate derivatives was determined by gas and liquid chromatography, and the yield was calculated for the aniline derivatives of formula (I).

Example 1 3-Trifluoromethylaniline (g) is mixed with 50 g of chlorobenzene, saturated with dry hydrochloric acid gas at 0.10 ° C, diisobutylcarbamoyl chloride (20 g) is added and the solution is heated to 50 ° C. . At this temperature, the mixture is reacted with 15 g of phosgene for 30 minutes and then stirred for a further 10 minutes.

After removal of the phosene, the resulting reaction mixture weighed 78.0 g.

3-trifluoromethylphenyl isocyanate content: 10.5% Yield: 98.0%.

Example 2

At a temperature below 5 ° C, 10 g of 4-chloro-3-trifluoromethylaniline are added dropwise to 100 g of dimethylcarbamoyl chloride, and 20 g of liquid phosgene are added at this temperature. The temperature was then gradually raised to 50 ° C over 30 minutes and then stirred for a further 20 minutes. Excess phosgene is removed by a stream of nitrogen.

After the phosgene removal the mass of the reaction mixture is:

111.3 g.

4-chloro-3-trifluoromethylphenyl isocyanate content: 10.1% Yield: 99.0%.

Example 3

In a 1: 1 mixture of dichlorobenzene (100 g) and diisopropylcarbamoyl chloride (1: 1), 10 g of 4-chloroaniline are dissolved at a temperature below +3 'C and at this temperature 15 g of phosgene are condensed in the mixture. The temperature of the reaction mixture was raised to 50 ° C over 30 minutes, and after 20 minutes post-mixing, excess phosgene was removed.

The weight of the resulting reaction mixture was 112 g. 4-chlorophenyl isocyanate content: 10.7%.

Yield: 99.2%.

Example 4

100 g of di-n-propylcarbamoyl chloride, 12 g of 4-chloro-3-trifluoromethylaniline hydrochloride and 15 g of liquid phosgene are weighed into a pressure vessel. After sealing the vessel, the temperature of the mixture was raised to 50 ° C and, after a reaction time of 20 minutes, excess phosgene and the resulting hydrochloric acid were blown off.

The resulting reaction mixture weighed 111.5 g. Contains 4-chloro-3-trifluoromethylphenyl isocyanate:

10.3%.

Yield: 99.1%.

Example 5

13 g of 3,4-dichloroaniline hydrochloride was added to 100 g of morpholino-carbamoyl chloride and then 15 g of phosgene was added with continuous stirring, raising the temperature to 35 ° C. Stir for another 10 minutes. and removing excess phosgene at the end of the reaction.

-5HU 201518 Β

The weight of the resulting reaction mixture was 112 g.

3.4-dichlorophenyl isocyanate content: 10.9%. Yield: 99.2%.

She. example

Dissolve 25 g of 3-chloroaniline in 100 g of o-dichlorobenzene and transfer to 50 g of diethyl carbamoyl chloride at 80 ° C in parallel with 30 g of phosgene. After stirring for 20 minutes, the excess phosgene was removed.

The resulting reaction mixture weighed 180 g.

3-chlorophenyl isocyanate content: 16%.

Yield: 95.8%.

Example 7

To a mixture of 100 g of a 1: 1 mixture of di-n-propylcarbamoyl chloride and diisopropylcarbamoyl chloride was added 15 g of 4-chloroaniline hydrochloride and the mixture was added at 40 ° C for 30 minutes. 25 g of phosgene are post-mixed for 10 minutes and excess phosgene is removed.

The weight of the resulting reaction mixture was 114 g.

4-chlorophenyl isocyanate content: 12.2%.

Yield: 99.1%.

Example 8 To 10 g of chlorobenzene is added 10 g of aniline hydrochloride. and 10 g of diethylamine and 40 g of phosgene (diethylamine and phosgene to form diethylcarbamoyl chloride, which is also a catalyst and a solvent) are added in parallel over 30 minutes at +5 ° C. The mixture was then heated to 80 ° C. at this temperature, it is reacted for a further 30 minutes. and then degassed.

The resulting reaction mixture weighed 107 g.

Phenyl isocyanate content: 8.5%.

Yield: 98.2%.

Example 9

Dissolve 170 g of chlorobenzene in 20 g of 80:20

2.4-diaminotoluene and 2,6-diaminotoluene. The solution was added to 70 g of dimethylcarbamoyl chloride over 30 minutes at 70 ° C in parallel with 60 g of phosgene. After 20 minutes post-mixing and subsequent phosgene removal, the reaction mixture weighed 232 g. Toluene diisocyanate content: 11.94%.

Yield: 97%.

Example 10

A solution of 15 g of 4,4'-diaminodiphenylmethane in 100 g of diethyl carbamoyl chloride is saturated with dry hydrochloric acid gas at a temperature below + 5 ° C and then reacted with 30 g of phosgene at 50 ° C for 30 minutes.

The reaction mixture obtained after the phosgene removal had a fill volume of 119 g.

4.4'-diphenylmethane diisocyanate content: 16%. Yield: 99.3%.

Example 11

15 g of 4-isopropylaniline hydrochloride are suspended in 100 g of a 80:20 mixture of chlorobenzene and dimethylcarbamoyl chloride. then 30 g of phosgene was added over a period of 40 minutes at 70 ° C. Stir for 20 minutes. then degassed.

Weight of reaction mixture: 114 g.

4-isopropylphenyl isocyanate content: 12%. Yield: 97%.

Example 12

Weigh 15 g of aniline hydrochloride and 1.7 g of N-phenyl-N ', N'-dimethylurea catalyst in 85 ml of chlorobenzene, then add 50 g of gaseous phosgene at 55-65 ° C for 3 hours. After 30 minutes of reaction, and after deionization of hydrochloric acid and phosgene, the reaction mixture weighed 110 g.

Phenyl isocyanate content: 12.5%.

Yield: 99%.

Example 13

15 g of 3,4-dichloroaniline hydrochloride and 2 g of N-phenyl-N ', N'-dimethylurea catalyst are added to 85 ml of chlorobenzene. At 60-80 'C, 50 g of gaseous phosgene are introduced into the reaction mixture over 3 hours, after which it is post-stirred at 80' C for 1 hour and degassed.

The resulting reaction mixture weighed 110 g.

3,4-dichlorophenyl isocyanate content: 12.7%. Yield: 98%.

Example 14

15 g of 3-trifluoromethylaniline hydrochloride and 2 g of N- (3-trifluoromethylphenyl) -N ', N'-diethylurea catalyst are added to 100 ml of chlorobenzene. A total of 60 g of phosgene was added over 4 hours to the reaction mixture at 80-90 ° C. After 1 hour of reaction and degassing, the resulting reaction mixture was 130 g.

3-trifluoromethylphenyl isocyanate content: 11%. Yield: 98%.

Example 75 Into a necked flask equipped with a stirrer, a thermometer, a gas inlet and a reflux condenser was introduced 150 ml of dichloroethane solvent and 7.5 g of phosgene was introduced at 25 ° C. A solution of 63.7 g of 4-chloroaniline and 1.5 g of dimethylformamide in 250 ml of dichloroethane was then added dropwise to the flask over 80 minutes. After further introduction of phosgene, boil for 40 minutes until the solution is clear. Hydrochloric acid and excess phosgene were evacuated with dry nitrogen and the solvent was distilled off. Weight of the pan: 70.0 g.

Composition: 92.1% 4-chlorophenyl isocyanate

3.7% bis (4-chlorophenyl) urea

1.3% 4-chloroaniline hydrochloride 2.9% other impurities.

Yield: 84.0%.

Example 76

In an apparatus similar to Example 15, 1.5 g of tetramethylurea are added to 150 ml of dichloroethane to initiate phosgenation (7.5 g of phosgene is introduced at 25 ° C). A solution of 63.7 g of 4-chloroaniline in 250 ml of dichloroethane was then added dropwise over 50 minutes and the mixture was heated under reflux for 40 minutes. After blowing off, solvent is removed. Weight of the cuvette: 71.2 g.

Composition: 88.11% 4-chlorophenyl isocyanate 11.89% other impurities.

Yield: 81.7%.

HU 201518 Β

Example 17

150 ml of dichloroethane are added to the apparatus described in Example 15, 2.5 g of Hexamethyleneimine are added, and 7.5 g of phosgene are introduced into the solution at room temperature. A solution of 63.7 g of 4-chloroaniline in 250 ml of dichloroethane is added dropwise over 50 minutes. Bring to the boil for a further 40 minutes (until the solution clears) with continuous phosgene. Hydrochloric acid and phosgene were stripped off with dry nitrogen and the solvent was distilled off under normal pressure.

Cuvette residue: 74 g.

Composition: 93.2% 4-chlorophenyl isocyanate 6.8% other impurities.

Yield: 89.8%.

Example 18

Carried out as in Example 16. with the exception that 18 g of N, N-dicyclopentamethyleneurea are used as a catalyst instead of 1.5 g of tetramethylurea. After solvent removal, the residue weighs 72%. Composition: 80.8% 4-chlorophenyl isocyanate 19.2% other impurities.

Yield: 75.8%.

15-18. Examples are disclosed in HU 159 106. No. 4,619,121, and reproduce the reaction with the catalysts described in U.S. Pat. (This patent does not give the active ingredient content, only the yield.)

15-18. examples

- the content of the active substances was determined by an internal standard method for liquid chromatography,

- other impurities means more than unidentified impurities other than bis (4-chlorophenyl) urea and 4-chloroaniline hydrochloride,

- after solvent removal, the samples did not contain solvent,

- the exposure values are given taking into account the active substance content,

- the storage stability of the samples is poor, with 3-10% further decrease in drug content over one month.

Example 19 In a necked flask equipped with a stirrer, a thermometer, a gas inlet and a reflux condenser was charged 200 ml of chlorobenzene and heated to 120-125 ° C. Phosgene was introduced into the solvent at a rate of 1 g / min for 15 min and 0.2 g of hexamethylene iminocarbamoyl chloride catalyst was added. A solution of 127.5 g of 4-chloroaniline in 680 ml of chlorobenzene is then added in parallel with the introduction of phosgene over a period of 2 to 2.5 hours.

After addition, phosgene was added for a further 15 minutes and the free hydrochloric acid and excess phosgene were purged with dry nitrogen. The solvent was evaporated in vacuo (100 torr) to give 154 g of 4-chlorophenyl isocyanate.

Fp. 88 'C / 1.33 kPa.

Active ingredient content: 98.7%.

Yield: 99%.

Example 20

The apparatus described in Example 19 was charged with 300 ml of chlorobenzene and heated to 125-130 ° C. Phosgene was introduced at a rate of 1 g / min for 20 min, and 0.3 g of hexamethylene iminocarbamoyl chloride catalyst was added. A solution of 162 g of 3,4-dichloroaniline in 700 ml of chlorobenzene is then added in parallel with the introduction of phosgene over a period of 2 to 2.5 hours. After addition, the mixture is phosgeneed for an additional 15 minutes and the excess phosgene and the hydrochloric acid formed are purged with dry nitrogen. The solvent was distilled off in a vacuum of 50 torr.

Weight of 3,4-dichlorophenyl isocyanate: 186.6 g.

Fp: 97 ° C / 1.33 kPa.

Active ingredient content: 98.9%.

Yield: 98.2%.

Example 21

Example 20 is repeated except that 1.7 g of hexamethylenimino-carbamoyl chloride is used instead of 0.3 g of hexamethyleniminocarbamoyl chloride. The temperature of the addition of 3,4-dichloroaniline is 95-100 ° C. After a further 15 minutes, the mixture was phosgeneed, and then with dry nitrogen, the hydrochloric acid and excess phosgene were blown off.

The 3,4-dichlorophenyl isocyanate obtained after distilling off the solvent had a mass of 187.8 s.

Fp: 97 'C / 1.33 kPa.

Active ingredient content: 98.1%.

Yield: 98.0%.

Examples 20 and 21 demonstrate that the temperature to be used can be reduced by increasing the amount of catalyst. The lower temperature is advantageous because in industrial scale production this means significantly less heat, other (cheaper, easier to distill) solvents, simpler equipment, which makes the production more economical.

Example 22

No. 19 200 ml of toluene are weighed into the apparatus of example. 0.15 g of hexamethylene iminocarbamoyl chloride and 1 g / min of phosgene were introduced for 15 minutes while heating to 105-110 ° C. A solution of 93 g of aniline in 650 ml of toluene was then added in parallel with phosgene introduction over a period of 2-2.5 hours. After addition, phosgene was added for a further 15 minutes and the hydrochloric acid and excess phosgene were purged with dry nitrogen. The solvent was distilled off in a vacuum of 100-200 torr.

Weight of product is 120 g of phenyl isocyanate.

Fp. 165 ° C active ingredient content: 98.4%.

Yield: 99.2%.

Example 23

No. 19 250 ml of o-dichlorobenzene and 0.3 g of dimethylcarbamoyl chloride were charged into the apparatus described in Example 1b. While stirring, it was heated to 115-120 ° C and phosgene was added to the reaction mixture at a rate of 1 g / min for 15 min. A solution of 161 g of 3-trifluoromethylaniline in 650 ml of o-dichlorobenzene was added in parallel with phosgene introduction over 2-2.5 hours. After addition, the mixture was phosgened for an additional 15 minutes. then the hydrochloric acid formed and the excess

-7GB 201518 Β Phosgene is blown with dry nitrogen. The solvent was distilled off in a vacuum of 50 torr. 3-Trifluoromethylphenyl isocyanate: 186 g.

Fp: 54 'C / 1.466 kPa.

Active ingredient content: 98.0%.

Yield: 97.5%.

Example 24

No. 19 350 ml of toluene and 0.2 g of dipropylcarbamoyl chloride catalyst were charged and phosgene was introduced with stirring at a rate of 1 g / min. Meanwhile, the toluene is heated to 90-95 ° C. A solution of 135 g of 4-i-propylaniline in 750 ml of toluene was started in parallel with the introduction of phosgene. The addition is carried out at a rate such that the aniline solution is added over 1.5-2 hours. Phosgene is then added for a further 15 minutes, and the hydrochloric acid and excess phosgene are purged with dry nitrogen. The toluene was distilled off in a vacuum of 150 torr.

The resulting 4-i-propylphenyl isocyanate had a mass of 162.2. Fp: 100 'C / 2 kPa.

Active ingredient content: 98.0%.

Yield: 98.6%.

Example 25

The apparatus described in Example 19 was charged with 300 ml of toluene and 0.2 g of hexamethyleniminocarbamoyl chloride, heated to 115-120 ° C with stirring, and phosgene was added at a rate of 1 g / min. thereafter

A solution of 108 g of m-toluidine in 700 ml of toluene was added dropwise over 2-2.5 hours in parallel with the addition of phosgene. After the addition, the phosgene is continued for 15 minutes. The hydrochloric acid and excess phosgene are then blown out with dry nitrogen. The toluene was distilled off in a vacuum of 100 torr.

The resulting m-tolyl isocyanate had a mass of 133 a.

Fp: 75 ° C / 1.59 kPa.

Active ingredient content: 98.1%.

Yield: 97.4%.

Example 26

Into the apparatus described in Example 19, 400 ml of dimethylcarbamoyl chloride were weighed, heated to 45 ° C with stirring, and phosgene was added at a rate of 1 g / min for 15 minutes. A solution of 162 g of 3,4-dichloroaniline in 590 ml of chlorobenzene is then added in parallel with the addition of phosgene over 2-2.5 hours at 45-50 ° C. After addition, the reaction mixture is phosgeneed for another 15 minutes. The hydrochloric acid and excess phosgene are then blown out with dry nitrogen. Chlorobenzene and dimethylcarbamoyl chloride are distilled off in a vacuum of 50 torr.

The resulting 3,4-dichlorophenyl isocyanate had a weight of 187.6.2.

· Potency. 97.2%.

Yield: 96.7%.

Example 27

Weigh 200 kg of anhydrous chlorobenzene into a 1250 liter autoclave. Gaseous phosgene is introduced at a flow rate of 2 m '/ h for 10 minutes. then 800 kg of a mixture of 14.1% 3-trifluoromethylaniline was introduced into the autoclave. parallel to the gaseous phosgene. 100 ° C for about 8 hours. A solution of 3-tri8 fluoromethylaniline in chlorobenzene contains 0.11% hexamethyleneimino-carbamoyl chloride catalyst.

A total of 100 kg of phosgene was introduced. After the addition, post-agitation was applied for 2 hours and then the autoclave was pressurized under reduced pressure to remove the reaction mixture from the reaction mixture for ca. 250 kg are distilled off.

The residue was about 750 kg, containing 16.9% 3-trifluoromethylphenyl isocyanate.

Yield: 96.7%.

Example 28

100 g of chlorobenzene containing 2.8% phosgene

A total of 40 g of gaseous phosgene and 200 g of a solution of 20.2% 3,4-dichloroaniline and 0.1% N-ethyl-N-cyclohexylcarbamoyl chloride in chlorobenzene are passed in 3 to 3.5 hours. C. After the addition, the mixture was post-stirred at 95-100 ° C for 30 minutes, then the excess phosgene was removed by an inert gas stream. hydrochloric acid formed during the reaction.

Weight of reaction mixture: 295 g.

Contains 3,4-dichlorophenyl isocyanate: 18.9%. Yield: 96.3%.

Example 29 To 50 g of liquid phosgene was added to 0 g of chlorobenzene 0-5. While maintaining the reaction mixture at 0.5 ° C, it was slowly cooled to ca. 100 g of a mixture of 15% 3-chloroaniline and 0.1% di-allylcarbamoyl chloride catalyst in chlorobenzene are added over 1 hour. A thick suspension forms. The temperature of the reaction mixture was raised to + 85-95 ° C over about 30 minutes. The precipitate dissolves. After stirring for 1 hour at 95 ° C, hydrochloric acid and phosgene deprotection, the resulting reaction mixture weighed 152 g.

Content of 3-chlorophenyl isocyanate: 11.5%.

Yield: 96.8%.

Example 30 To 40 g of liquid phosgene in 0 g + 0 ° C of chlorobenzene was added 0.3 g of N-ethyl-N-phenylcarbamoyl chloride catalyst and 140 g of 22.1% g. aniline-containing chlorobenzene solution. The temperature of the reaction mixture is about 10 minutes. After 2 hours, the mixture was raised to 110 ° C and after 1 hour of stirring, followed by hydrochloric acid and de-phosgene removal, the resulting reaction mixture weighed 215 g.

Content of phenyl isocyanate: 17.1%.

Yield: 92%.

EXAMPLE 31 A parallel mixture of 80 g of phosgene and 250 g of 17.2% of 3-chloroaniline and 0.1% of diethylcarbamoyl chloride in chlorobenzene was added at 110 ° C to a volume of ca. In 3 hours. After stirring for 1 hour at 115 ° C, followed by the removal of hydrochloric acid and phosgene, the resulting reaction mixture weighed 305 g.

3-chlorophenyl isocyanate content: 16.1%.

Yield: 95%.

Example 32 20 g of phosgene are added in parallel to g of toluene at 0 + 5 'C. 200 g of 4-bromoaniline

HU 201518 Β

13.2% toluene in about 2-2.5 hours with vigorous cooling and stirring. After the addition was complete, 0.2 g of bis / 2-chloroethylcarbamoyl chloride catalyst was added to the reaction mixture. then, with additional 15 g of phosgene, the temperature of the reaction mixture was raised to the boiling point of toluene (111 'C) over a period of about 2 hours, while the precipitate formed in the previous step was dissolved. After removal of hydrochloric acid and phosgene, the content of 4-bromophenyl isocyanate is 10.4%. Yield: 97%.

Example 33

No. 19 Chlorobenzene (1000 ml), 3-trifluoromethylaniline hydrochloride (197.5 g) and Fluometuron (N- (3-trifluoromethylphenyl) -N, N-dimethylurea) (4 g) were charged and the mixture was heated to 100-110 ° C with stirring. Phosgene was then introduced at a rate of 1 g / min

2 to 2.5 hours (phosgene for another half hour after purification). The excess phosgene and the resulting hydrochloric acid were then purged with dry nitrogen and the solvent was distilled off in a vacuum of 100 torr. The product

3-trifluoromethylphenyl isocyanate weighed 188 g.

Fp: 54 'C / 1.466 kPa.

Active ingredient content: 97.8%.

Yield: 98.3%.

Example 34

No. 19 Into the apparatus described in Example 1b, 200 ml of chlorobenzene, 1 g of phenuron (N-phenyl-N, N-dimethylurea) were charged and heated to 110-115 ° C with stirring. Meanwhile, phosgene was introduced into the mixture at a rate of 1 g / min for 20 minutes. A solution of 93 g of aniline in 550 ml of chlorobenzene was then added dropwise over 2 hours in parallel with the introduction of phosgene. Phosgene was added to the reaction mixture for a further 30 minutes, and the hydrochloric acid and excess phosgene were purged with dry nitrogen. The solvent was evaporated in a vacuum of 100 torr.

Weight of the resulting phenyl isocyanate: 117 g. Fp. 165 'C. Active ingredient content: 97.8%.

Yield: 96.1%.

Claims (10)

PATENT CLAIMS A process for the preparation of phenyl (di) isocyanate derivatives Aniline derivatives of the formula I wherein n is 1 or 2, R and R j are hydrogen or halogen, straight or branched C 1 -C 4, optionally halogen mono- or polysubstituted alkyl groups, and (C 1 -C 2 alkyl) anilino groups, or their hydrochloric acid salts with phosgene, optionally in the presence of a catalyst, in the presence of a catalyst, a) aniline derivatives of formula I wherein the substituents are as defined above or their hydrochlorides are 1 to 10 times the (disubstituted) carbamoyl chloride of formula II wherein R 2 and R 3 are 1 C4 -C4 linear or branched alkyl. or, together with the nitrogen atom, either alone or in an inert organic solvent, preferably an aliphatic or aromatic hydrocarbon, mixed in any proportion (or mixture), or b) the aniline derivatives of formula I wherein the substituents are as defined above, or their hydrochlorides in 1-10 times the amount of the inorganic organic solvent, preferably a halogenated aliphatic or aromatic hydrocarbon, and from 0.05 to 5 relative to the aniline, 0% by weight of disubstituted carbamoyl chloride of formula II, wherein the substituents are as defined above, or 0.5 to 15% by weight of trisubstituted urea of formula (etben), wherein R 4 is hydrogen or halogen, C 1 -C 4 straight or branched chain alkyl, optionally mono- or polysubstituted by halogen, and R5 and R6 are reacted with phosgene at atmospheric pressure or 0-5 bar in the presence of a C 1-4 straight or branched alkyl alkyl catalyst at a temperature of 0-120 ° C and The resulting phenyl (di) isocyanate derivative is known from the reaction mixture Preferably, the reaction mixture is recovered by purging with phosgene and hydrochloric acid, by vacuum distillation and by solvent removal. (Priority: 15.1.1985) Process according to claim 1, characterized in that the aniline derivative of formula (I) wherein the substituents have the meanings given above - or its hydrochloride at 0-4-5 ° C - is 1-10 times (Π) in the (disubstituted) carbamoyl chloride (s) of the general formula wherein the substituents have the meaning given above - dissolved and reacted with phosgene at a temperature between 30-50 ° C. (Priority: 15.1.1985) 3. A process according to claim 1, wherein the aniline derivative of the Formula I wherein the substituents are as defined above or its hydrochloride is dissolved in 5 to 10 times the amount of the inert organic solvent, preferably chlorobenzene, - 1 to 10 ° C - 1 to 5 times the amount of the disubstituted carbamoyl chloride of the formula II, relative to the aniline - wherein the substituents have the meaning given above reacting with phosgene in the presence of a catalyst at a temperature of 50-80 ° C. (Priority: 15.1.1985) The process of claim 1 wherein the aniline derivative (s) of formula (I) wherein the substituents have the meanings given above - or their hydrochloride (s) - in 4 to 10 times the amount of the inert organic solvent, preferably (di) chlorobenzene, at a temperature of 4080 ° C, parallel to the phosgene, The disubstituted carbamoyl chloride of formula (II), wherein the substituents have the meanings given above, is introduced and post-reacted until the formation of the target product is complete. (Priority: 15.1.1985) The process of claim 1, wherein the aniline derivative of formula (I) wherein the substituents are as defined above, or its hydrochloride is dissolved in a 1 to 10 fold amount of a solvent mixture of (1: 1) to (4). 1) organic solvent, preferably (di) chlorobenzene, and disubstituted carbamoyl chloride of formula (II), wherein the substituents have the meanings given above: containing phosgene is introduced into the solution at a temperature between 0-4-30 'C and HU 201518 Β raised to 50-70 ° C and post-agitated. (Priority: 15.1.1985) 6. A process according to claim 1, wherein the aniline derivative of the formula I wherein the substituents are as defined above, or its hydrochloride is dissolved in 5-6 times the amount of the inert organic solvent, preferably (di) chlorobenzene or toluene. and adding the solution to a phosgene-inorganic organic solvent, preferably the same, in which phosgene was previously introduced by heating to 90-120 ° C and from 0.1 to 1.2% by weight of the disubstituted formula II relative to the aniline. Carbamoyl chloride, wherein the substituents have the meanings given above, was measured. and after completion of the addition and post-reaction, the target product is recovered from the reaction mixture in a known manner. (Priority: 15.1.1985) 7. A process according to claim 1, wherein the aniline derivative of formula I, wherein the substituents are as defined above, or its hydrochloride in 2 to 10 times the amount of the inert organic solvent, is preferably dissolved in chlorobenzene or toluene. 0.4-1.1% by weight of the disubstituted carbamoyl chloride of the formula 11, where the substituents are as defined above, and then the solution containing the catalyst, preferably in parallel with the phosgene, in an inert organic solvent. , in which liquid phosgene was previously added at 0-5 ° C or gaseous at 20-110 ° C and the aniline was reacted with phosgene at 85-110 ° C. (Priority: 15.1.1985) 8. A process according to claim 1, wherein the aniline derivative of the formula I, wherein the substituents are as defined above, or the hydrochloride thereof is dissolved in 5 to 10 times the amount of the inert organic solvent, preferably chlorobenzene. 2 to 15% by weight of the trisubstituted urea of the formula (III) in which the substituents are as defined above, followed by reaction with phosgene at 50-110 ° C. (Priority: 15.1.1985) 9. A process according to claim 1, wherein the aniline derivative of formula I wherein the substituents are as defined above or its hydrochloride is dissolved in 5 to 8 times the amount of the inert organic solvent, preferably chlorobenzene, and the solution is dissolved in phosgene. is added in parallel to an inert organic solvent, preferably the same as the former, in which 0.5 to 2.0% by weight of the trisubstituted urea of the formula (III), wherein the substituents have the meanings given above, are added thereto. While heating to 120 ° C, phosgene was introduced and after the addition and post-reaction was complete, the target product was recovered from the reaction mixture. (Priority: 15.1.1985) A process for the preparation of phenyl (di) isocyanate derivatives Aniline derivatives of formula I wherein n is 1 or 2 and R and R 1 are hydrogen or halogen. C 1-4 -alkyl, linear or branched, optionally substituted singly or multiply by halogen, and (C 1-2 -alkyl) -anilino - or their hydrochloride salts with phosgene in a solvent medium, optionally in the presence of a catalyst characterized by a) aniline derivatives of formula I wherein the substituents are as defined above, or their hydrochlorides, in an amount of 1 to 10 times the disubstituted carbamoyl chloride of formula II, wherein R 1 and R ₃ are halogen, or C 1-4 -alkyl, C 2-4 -alkenyl, mono- or polysubstituted by hydroxy. C 3 -C 6 cycloalkyl or phenyl, and R ₂ and R 3 taken together with the nitrogen atom, alone or in an inert organic solvent, suitably halogenated aliphatic or aromatic hydrocarbon, are dissolved in any solvent or mixture; b) the aniline derivatives of the formula I wherein the substituents are as defined above, or their hydrochlorides in 1-10 times the amount of the inert organic solvent, preferably a halogenated aliphatic or aromatic hydrocarbon, and 0.05-5.0 relative to the aniline by weight of the disubstituted carbamoyl chloride of formula II, wherein the substituents are as defined above, in the presence of a catalyst at a temperature of 0 to 120 ° C, at atmospheric pressure or at a pressure of 0 to 5 bar, with phosgene. and recovering the resulting phenyl (di) isocyanate derivative from the reaction mixture in a known manner, preferably by purifying the reaction mixture by blowing off phosgene and hydrochloric acid, and removing the solvent by vacuum distillation.