DD159637A5 - ACYLATIVES FOR ACYLATING PHENOLIC HYDROXYL GROUPS - Google Patents

Abstract

The invention relates to a novel acylating agent for the acylation of phenolic hydroxyl groups which, according to the invention, contains 5 to 50% by weight of a saccharin compound of the general formula IV as the acylating agent. In formula IV, R is an alkyl group of 1 to 8 carbon atoms, an acyl group, a cycloalkyl group of 5 or 6 carbon atoms, an aralkyl group of 7 to 15 carbon atoms, or the alkyl-mono- or polysubstituted derivatives of these groups. Further, the agent contains 0.2 to 30 wt .-% of a base and 10 to 80 wt .-% solvent. The base, based on the acylating agent, must be present in at least an equivalent amount. Preferred acylating agents are N-Phe4nylcarbamoyl-benzoic acid sulfimide, N-methylcarbamoylbenzoic acid sulfimide, N-butylcarbamylbenzoic acid sulfimide or N- (methylphenyl) -carbamoylbenzoic acid sulfimide. The solvent used is preferably acetone and preferably triaethylamine as the base. The acylating agent is preferably suitable for the preparation of certain, suitable as crop protection agents carbamic acid phenyl ester derivatives. Formula IV

Description

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230915

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Acylating agent for the acylation of phenolic hydroxyl groups

Field of application of the invention:

The invention relates to a novel, suitable for the acylation of phenolic hydroxyl groups acylating agent.

Characteristic of the known technical solutions:

There are known Carbaminsäurephenylester of the general formula I, wherein

R is an alkyl group having 1 to 8 carbon atoms, an aryl group, a cycloalkyl group having 5 or 6 carbon atoms or an aralkyl group having 7 to 16 carbon atoms, and the derivatives of these groups mono- or polysubstituted by alkyl,

R is hydrogen, an alkyl or an alkoxy group having 1 to 4 carbon atoms or acylamino group, 2

R is hydrogen, halogen, an alkyl or an alkoxy group having 1 to 4 carbon atoms, wherein the

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With

1 2 R and R designated alkyl and / or alkoxy groups can be closed via a C-C bond to the ring.

The majority of the compounds of general formula I is used in agriculture as a plant protection agent.

It is generally known that the compounds of general formula I preferably by addition of isocyanates of general formula III to phenol derivatives of the general formula II (in the formulas II and III is the meaning of

1 2

R, R and R are the same as above). A disadvantage of this method is that the highly toxic and the mucous membranes attacking isocyanates pose health and safety problems, which also greatly complicates the manufacturing process. Another disadvantage is the highly exothermic nature of the addition reaction, which raises further technological problems especially in isocyanates with a low boiling point or brings with it the risk of undesirable side reactions. The Trnasport and the storage of different isocyanates require special measures and special packaging units, which causes additional costs. The possibility of acquiring isocyanates is limited on a global scale.

The compounds of general formula I could in principle also be prepared by reacting the compounds of general formula II with monosubstituted carbamic acid chlorides. However, in contrast to their disubstituted analogues, the monosubstituted carbamic acid chlorides are unstable substances which decompose to isocyanates with elimination of hydrochloric acid. These unstable compounds can also be formed by addition of hydrochloric acid to isocyanates, but it is unlikely that they are nucleophilic

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Agents, for example compounds of general formula II, without prior elimination of hydrochloric acid to acylate. The disadvantages mentioned in connection with the isocyanates moreover exist to an even greater extent for the monosubstituted carbamic acid chlorides.

Another possibility for the preparation of the compounds of general formula I is the reaction of the compounds of general formula II with phosgene and the subsequent acylation of the resulting chloroformate derivatives with amines of the general formula R-NHp to have to work extremely toxic phosgene gas.

Object of the invention:

With the invention, an improved process for the preparation of the compounds of formula I is to be made possible.

Explanation of the essence of the invention:

The invention has for its object to produce a novel agent for the acylation of phenolic hydroxyl groups.

It has been found that the carbamic acid phenyl ester derivatives of the general formula I can be obtained in novel manner in high purity and good yield, if the phenols of general formula II in the presence of a base with N-carbamoyl saccharin derivatives of general formula IV, wherein the meaning of R is the same as above, O-acylated.

The bases used may be inorganic bases, preferably alkali metal hydroxides, carbonates, bicarbonates, alkaline earth hydroxides,

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carbonates, bicarbonates, but also organic bases, such as tertiary amines, preferably triethylamine, can be used. The base is suitably used in at least the equimolar amount based on the acylating agent. The manufacturing process is the subject of the copending application AP C07 C / 224 988, from which this application was made.

The invention thus relates to an acylating agent suitable for the acylation of phenolic hydroxyl groups which, according to the invention, comprises 5 to 50% by weight of a compound of the general formula IV in which R is an alkyl group having 1 to 8 carbon atoms, an aryl group, a cycloalkyl group 5 or 5 6 carbon atoms or an aralkyl group having 7 to 16 carbon atoms and for the alkyl by single or multiple substituted derivatives of these groups. For this purpose, the agent contains 0.2 to 30 wt .-%, but based on the acylating agent at least the equimolar amount of a base and 10 to 60 wt.% Solvent.

A preferred embodiment of the acylating agent according to the invention contains as acylating agent N-phenylcarbamoyl-benzoic acid sulfimide, N-methyl-carbamoyl-benzoic acid sulfimide, N-butyl-carbamoyl-benzoic acid sulfimide or N- (methylphenyl) -carbamoyl-benzoic acid sulfimide and as Base triethylamine, while acetone is preferred as the solvent.

Embodiments;

The invention will be explained in more detail below with reference to examples.

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example 1

4.3 g (0.025 mol) of methyl N- (3-hydroxyphenyl) carbamate are dissolved in 15 ml of acetone in the presence of 2.56 g (0.025 mol) of triethylamine with 7.3 g (0.025 mol) of N-phenylcarbamoyl benzoic acid sulfimide (m.p .: 184-186 ⁰ C) at 40 ° C for 15 minutes implemented. The reaction mixture is mixed with 40 ml of water and cooled to 5 to 10 ⁰ C. After half an hour, the product is filtered off, washed and dried. There are obtained 5.5 g of S-methoxycarbonyl-aminophenyl-phenylcarbamate, which melts at 150 to 152 ⁰ C. The benzoic acid sulfimide can be precipitated from the mother liquor with hydrochloric acid.

Example 2

3.35 g (0.025 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol are dissolved in 15 ml of acetone in the presence of 2.56 g (0.025 mol) of triethylamine with 6 g (0.025 mol) of N ⁰ C for 15 minutes implemented methylcarbamoyl-benzoic acid sulfimide at 5O. The reaction mixture is diluted with 100 ml of water and cooled to room temperature. The deposited precipitate is filtered off, washed with water and then dried. There are obtained 3.1 g of 2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate, which melts at 150 to 152 C. The benzoic acid sulfimide can be regenerated from the mother liquor by acid precipitation.

Example 3

1.5 g of N-methylcarbamoyl-benzoic acid sulfimide are suspended in a mixture of 1 g of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol, 5 ml of acetone and 5 ml of water. At room temperature, 0.6 g of triethylamine dissolved in a mixture of 2 ml of acetone and 1 ml of water are added dropwise with stirring within 20 minutes. Then become the reaction mixture

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20 ml of water are added dropwise within 30 minutes. After stirring for 1 1/2 hours, the crystals are filtered off, washed with water and then dried. There are obtained 0.745 g of 2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate, which melts at 150 to 152 ⁰ C.

Example 4

4.3 g (0.025 mol) of methyl N- (3-hydroxyphenyl) carbamate are dissolved in 15 ml of acetone, in the presence of 2 g (0.0145 mol) of potassium carbonate with 7.3 g (0.025 mol) of N-phenylcarbamoyl- Benzoesäuresulfimid (mp: 184 to 186 ⁰ C) for 15 minutes at reflux refluxed. The reaction mixture is mixed with 40 ml of water and cooled to 5 to 10 ° C. After one hour, the precipitate is filtered off, washed and dried. There are obtained 5.8 g of S-Methoxycarbonylaminophenylcarbamat, which melts at 150 to 152 ° C.

Example 5

4.5 g (0.025 mol) of ethyl N- (3-hydroxyphenyl) carbamate are dissolved in 15 ml of acetone in the presence of 2.56 g (0.025 mol) of triethylamine with 7.3 g (0.025 mol) of N-phenylcarbamoylbenzoic acid ^ uresulfimid reacted at 40 C for 15 minutes. After addition of 40 ml of water, the mixture is cooled to 5 ⁰ C. After standing for 30 minutes, the product is filtered off, washed and dried. There are obtained 5.7 g of 3-Äthoxycarbonylaminophenyl-phenylcarbamate, which melts at 117 to 119 ⁰ C.

Example 6

4.3 g (0.025 mol) of methyl N- (3-hydroxyphenyl) carbamate are dissolved in 15 ml of acetone and in the presence of 2.56 g (0.025 mol) of triethylamine with 7.9 g (0.025 mol) of N- (3 -Methylphenyl) -carbamoylbenzoesäure-sulfimide at 30 ⁰ C for 30 minutes, After

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Addition of 50 ml of water, the mixture is cooled to 5 to 1O ⁰ C. After standing for 30 minutes, the product is filtered off, washed and dried. There are obtained 5.3 g of 3-Methoxycarbamoylphenyl-3'-methylphenylcarbamat, which melts at 140 to 142 ⁰ C. From the mother liquor can be regenerated by precipitation with hydrochloric acid 3.5 g (76 %) Benzoesäuresulfimid. This is possible with all of the above examples.

Example 7

5 g of N-methylcarbamoyl-benzoic acid-sulfimide are suspended in a mixture of 2.67 g of 2-chlorophenol and 50 ml of acetone, the suspension is cooled to 5 ⁰ C, and then with constant stirring dropwise, the solution of 2.9 ml Triethylamine in 30 ml of acetone added. During the addition (2 hours), the temperature of the mixture does not rise above

6C on. The reaction mixture is stirred at this temperature for 12 hours and then treated with 240 ml of distilled water. Then the mixture is extracted three times with 30 ml of ether. The combined ethereal extracts are dried over anhydrous sodium sulfate and then evaporated in vacuo at not more than 30 ⁰ C. There are obtained 3.13 g of N-methylcarbamic acid (2-chlorophenyl) ester, which melts after recrystallization from n-pentane at 90 to 910C.

Example 8

5 g of N-methylcarbamoyl-benzoic acid-sulfimide are suspended in a mixture of 2.6 g of 2-methoxyphenol and 50 ml of acetone. With constant stirring, the solution of 2.9 ml of triethylamine in 30 ml of acetone is added dropwise at room temperature within one hour. The reaction mixture is stirred for a further 2 hours at room temperature and then treated with 240 ml of distilled water. The mixture is extracted three times with 30 ml of ether. The united ethereal ex

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are dried over anhydrous sodium sulfate and then evaporated in vacuo at not more than 3O ° C. There are obtained 2.43 g of N-methylcarbamic acid (2-methoxyphenyl) ester, which melts after recrystallization from n-pentane at 90 to 92 ⁰ C.

Example 9

2.4 g of N-methylcarbamoyl-benzoic acid-sulfimide are suspended in a mixture of 1.63 g of 2-methoxy-4-cyanomethylene-phenol and 15 ml of acetone. With constant stirring, the solution of 1.4 ml of triethylamine in 5 ml of acetone is added dropwise to the suspension at room temperature within one hour. The mixture is stirred at room temperature for a further 2 hours and then treated with 65 ml of distilled water. The mixture is allowed to stand at 5 ^° C. for 16 hours, then the precipitated N-methylcarbamic acid (2-methoxy-4-cyanomethylphenyl) ester is filtered off and washed with 5 C warm water. There are obtained 0.72 g of product, which melts at 138 to 139 ° C. Elemental analysis: C% = 59.99 H% = 5.45 H% - 12.72 found: C% = 60.05 H% = 5.52 N% = 12.65

The mother liquor is washed three times with 10 ml of ether, the combined ethereal extracts are dried over anhydrous sodium sulfate and in vacuo at a maximum of 30 ° C eingedamp product obtained.

Example 10

30 C evaporated. In this way, another 0.95 g of pro-

5 g of N-butylcarbamic acid-benzoic acid sulfimide are suspended in a mixture of 1.67 g of phenol and 50 ml of distilled water. 0.71 g of sodium hydroxide in 50 ml of distilled water are added dropwise to the suspension at room temperature with constant stirring within 5 hours.

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given. The reaction mixture is stirred for a further three hours, then extracted three times with 30 ml of ether, and the combined ethereal extracts are dried over anhydrous sodium sulfate and then evaporated in vacuo at not more than 30 ^° C. There are obtained 2.15 g of N-Butylcarbaminsäurephenylester. Boiling point: 146 to 165 ° C / 2 Torr.

Example 11

5 g of N-tert-butylcarbamoyl-benzoic acid sulfimide and 1.9 g of 4-methylphenol are heated in 50 ml of chloroform to the boiling point. Then 2.5 ml of triethylamine in 30 ml of chloroform are added dropwise with constant stirring within one hour. The mixture is boiled for one hour and then evaporated in vacuo. The oily residue is stirred with 100 ml of ether. The precipitated Benzoesäuresulfimidtriäthylamin salt is filtered off and the filtrate is evaporated in vacuo at not more than 30 ⁰ C. There are obtained 2.4 g of N-tert-Butylcarbaminsäure- (4-methyl-phenyl) ester, which melts after recrystallization from petroleum ether at 130 to 132 ° C.

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2 3 0 9 15 0

0-C-NH-R

Il

(I)

R ²

OH

(H)

R-N = OO-

(3H)

N-C-NH-R

so / I

λ ο uiK -IQfH * Μώ Ί'765

Claims (3)

- »- 230915 0 invention claim 1. An acylating agent for the acylation of phenolic hydroxyl groups, characterized in that it contains as acylating agent 5 to 50 wt .-% of a saccharin compound of the general formula IV, wherein R is an alkyl group having 1 to 8 carbon atoms, an aryl group, a cycloalkyl group having 5 or 6 carbon atoms or an aralkyl group having 7 to carbon atoms, and represents the alkyl-mono- or polysubstituted derivatives of these groups, 0.2 to 30 wt .-% However, based on the acylating agent, at least the equivalent amount of a base and 10 to 80 wt .-% solvent. 2. acylating agent according to item 1, characterized in that it contains as the acylating agent N-phenylcarbamoyl-benzoesäuresulfimid, N-methylcarbamoyl-benzoesäurefulfimid, N-butylcarbamoyl-benzoesäuresulfimid or N- (methylphenyl) -carbamoyl-benzoesäuresulfimid. 3. acylating agent according to item 1 and 2, characterized in that it contains acetone as solvent and triethylamine as base. For this 1 sheet of formulas