GB2106501A

GB2106501A - Method for making benzoylphenylureas

Info

Publication number: GB2106501A
Application number: GB08128336A
Authority: GB
Inventors: David Philip Clifford; Robert Arthur Sewell
Original assignee: Dow Chemical Co Ltd; Dow Chemical Co
Current assignee: Dow Chemical Co Ltd; Dow Chemical Co
Priority date: 1981-09-18
Filing date: 1981-09-18
Publication date: 1983-04-13
Also published as: GB2106501B

Abstract

A process for preparing a compound having the formula: <IMAGE> wherein X and Y are individually H, F, Cl, alkyl or haloalkyl; R and R' are individually H, halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, nitro or cyano, wherein T is halogen, halogenated alkyl or the group ZR'' wherein R'' is H, alkyl, aryl, alkyl, halogenated alkyl, halogenated alkylene, pyridyo, substituted pyridyl, phenyl or substituted phenyl and Z is O or S, comprises reacting a benzoyl chloride with an alkali metal cyanate in the presence of a catalyst and an inert solvent to prepare a benzoyl isocyante which is treated in situ with an appropriate aniline compound.

Description

SPECIFICATION Method for making benzoylphenylureas This invention relates to a method for making benzoylphenylureas and, more particularly, relates to a novel process comprising reacting a benzoyl chloride with an alkali metal cyanate to prepare a benzoyl isocyanate which is then treated in situ with an appropriate aniline compound to give the desired benzoylphenylurea.

More specifically, the present invention comprises a process for making a compound having the formula:-

wherein X and Y are individually H,F,CI, alkyl or haloalkyl; R and R' are individually H, halogen, alkyl haloalkyl, alkoxy, haloalkoxy, nitro or cyano, wherein T is halogen, halogenated alkyl or the group ZR" wherein R" is H, alkyl aryl, alkyl, halogenated alkyl, halogenated alkylene, pyridyl, substitueted pyridyl, phenyl or substituted phenyl and Z is O or S, which comprises reacting a benzoyl chloride with an alkali metal cyanate in the presence of a catalyst and an inert solvent to prepare a benzoyl isocyanate which is treated in situ with an appropriate aniline compound.

The benzoyl chloride used in the process of this invention is advantageously prepared by the reaction of chlorine with the appropriate benzaldehyde in the presence of phosphorus pentachloride as described in Application Number 79,36243, filed 18th October 1979.

The aniline compound used in the process of this invention is advantageously prepared by reacting a phenol compound having the formula:-

wherein R and R' are as previously described with a haloethane, haloethylene, halobenzene or a halopyridine. This reaction is preferably carried out in a polar solvent in the presence of an alkali metal base, such as sodium or potassium hydroxide, at a temperature in the range of from -20 to 2200C, more preferably at a temperature in the range of from -5 to 25 OC. The preferred haloethylene is 1,1 1 ,1-dichloro-2,2-difluoroethylene.

While any alkali metal cyanate may be employed, the preferred cyanates are the sodium and potassium cyanates.

The preferred catalyst is cuprous chloride. The preferred solvent for use in both stage of the process of the invention is o-dichlorobenzene, xylene or chlorobenzene.

The first stage of the reaction is preferably carried out at a temperature in the range of from 100 to 2000 C, nore preferably at reflux temperature. The second stage of the reaction is preferably carried out at a temperature in the range of from 0 to 1000C, ambient temperature being most preferred.

The invention is further illustrated by the following examples.

Example 1 A slurry of sodium cyanate (2.23 g) in o- dichlorobenzene (15 ml), 2-chlorobenzoyl chloride (4.61 g) and cuprous chloride (0.25 g) was prepared and heated under reflux for 40 minutes. The hot reaction mixture was filtered to remove the solids and the clear filtrate was treated with excess 4-chlornaniline. The reaction mixture was made up to a known volume with methanol and the resulting solution was assayed against an external standard showing a yield of 50 percent of N-(2-chlorobenzoyl)-N'-(4 chlorophenyl)urea.

When the reaction was repeated under the same conditions using no solvent and with a reaction time of 5 to 60 minutes, no isocyanate was formed (IR). Similarly, the omission of the cuprous chloride catalyst resulted in no isocyanate being formed.

Example 2 A slurry of potassium cyanate (2.76 g) in o- dichlorobenzene (15 ml), cuprous chloride (0.25 g) and 2-clorobenzoyl chloride (4.61 g) was prepared and heated under reflux for 60 minutes.

The solids were removed by filtration and the clear filtrate was treated with excess (4-2,2 dichloro- 1,1 -difluoroethoxy)aniline. HPLC (high pressure liquid chromatography) analysis of the reaction mixture using an external standard showed a 40 percent yield of 2-chloro-N-(((4 (2,2-dichloro-1 ,1 -difluoroethoxy)phenyl)amino)carbonyl)benzamide.

Claims

1. A process for preparing a compound having the formula:-

wherein X and Y are individually H,F,CI, alkyl or haloalkyl; R and R' are individually H, halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, nitro or cyano; wherein T is halogen, halogenated alkyl or the group ZR" wherein R" is H, alkyl aryl, alkyl, halogenated alkyl, halogenated alkylene, pyridyl, substituted pyridyl, phenyl or substituted phenyl and Z is 0 or S, which comprises reacting a benzoyl chloride with an alkali metal cyanate in the presence of a catalyst and an inert solvent to

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Method for making benzoylphenylureas This invention relates to a method for making benzoylphenylureas and, more particularly, relates to a novel process comprising reacting a benzoyl chloride with an alkali metal cyanate to prepare a benzoyl isocyanate which is then treated in situ with an appropriate aniline compound to give the desired benzoylphenylurea. More specifically, the present invention comprises a process for making a compound having the formula:- wherein X and Y are individually H,F,CI, alkyl or haloalkyl; R and R' are individually H, halogen, alkyl haloalkyl, alkoxy, haloalkoxy, nitro or cyano, wherein T is halogen, halogenated alkyl or the group ZR" wherein R" is H, alkyl aryl, alkyl, halogenated alkyl, halogenated alkylene, pyridyl, substitueted pyridyl, phenyl or substituted phenyl and Z is O or S, which comprises reacting a benzoyl chloride with an alkali metal cyanate in the presence of a catalyst and an inert solvent to prepare a benzoyl isocyanate which is treated in situ with an appropriate aniline compound. The benzoyl chloride used in the process of this invention is advantageously prepared by the reaction of chlorine with the appropriate benzaldehyde in the presence of phosphorus pentachloride as described in Application Number 79,36243, filed 18th October 1979. The aniline compound used in the process of this invention is advantageously prepared by reacting a phenol compound having the formula:- wherein R and R' are as previously described with a haloethane, haloethylene, halobenzene or a halopyridine. This reaction is preferably carried out in a polar solvent in the presence of an alkali metal base, such as sodium or potassium hydroxide, at a temperature in the range of from -20 to 2200C, more preferably at a temperature in the range of from -5 to 25 OC. The preferred haloethylene is 1,1 1 ,1-dichloro-2,2-difluoroethylene. While any alkali metal cyanate may be employed, the preferred cyanates are the sodium and potassium cyanates. The preferred catalyst is cuprous chloride. The preferred solvent for use in both stage of the process of the invention is o-dichlorobenzene, xylene or chlorobenzene. The first stage of the reaction is preferably carried out at a temperature in the range of from 100 to 2000 C, nore preferably at reflux temperature. The second stage of the reaction is preferably carried out at a temperature in the range of from 0 to 1000C, ambient temperature being most preferred. The invention is further illustrated by the following examples. Example 1 A slurry of sodium cyanate (2.23 g) in o- dichlorobenzene (15 ml), 2-chlorobenzoyl chloride (4.61 g) and cuprous chloride (0.25 g) was prepared and heated under reflux for 40 minutes. The hot reaction mixture was filtered to remove the solids and the clear filtrate was treated with excess 4-chlornaniline. The reaction mixture was made up to a known volume with methanol and the resulting solution was assayed against an external standard showing a yield of 50 percent of N-(2-chlorobenzoyl)-N'-(4 chlorophenyl)urea. When the reaction was repeated under the same conditions using no solvent and with a reaction time of 5 to 60 minutes, no isocyanate was formed (IR). Similarly, the omission of the cuprous chloride catalyst resulted in no isocyanate being formed. Example 2 A slurry of potassium cyanate (2.76 g) in o- dichlorobenzene (15 ml), cuprous chloride (0.25 g) and 2-clorobenzoyl chloride (4.61 g) was prepared and heated under reflux for 60 minutes. The solids were removed by filtration and the clear filtrate was treated with excess (4-2,2 dichloro- 1,1 -difluoroethoxy)aniline. HPLC (high pressure liquid chromatography) analysis of the reaction mixture using an external standard showed a 40 percent yield of 2-chloro-N-(((4 (2,2-dichloro-1 ,1 -difluoroethoxy)phenyl)amino)carbonyl)benzamide. Claims

1. A process for preparing a compound having the formula:-

wherein X and Y are individually H,F,CI, alkyl or haloalkyl; R and R' are individually H, halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, nitro or cyano; wherein T is halogen, halogenated alkyl or the group ZR" wherein R" is H, alkyl aryl, alkyl, halogenated alkyl, halogenated alkylene, pyridyl, substituted pyridyl, phenyl or substituted phenyl and Z is 0 or S, which comprises reacting a benzoyl chloride with an alkali metal cyanate in the presence of a catalyst and an inert solvent to prepare a benzoyl isocyanate which is treated in situ with an appropriate aniline compound.

2. A process as claimed in claim 1 wherein X and Y are individually H, Cl or F; R and R' are individually H or Cl and T is chlorine, trifluoromethyl or ZR" wherein R" is hydrogen, chloro or fluoro substituted alkyl.

3. A process as claimed in claim 1 or claim 2 wherein the benzoylchloride is 2-chlorobenzoyl chloride.

4. A process as claimed in any one of the preceding claims wherein the alkali metal of the alkali metal cyanate is potassium or sodium.

5. A process as claimed in any one of the preceding claims wherein the catalyst is cuprous chloride.

6. A process as claimed in any one of the preceding claims wherein the solvent is odichlorobenzene.

7. A process as claimed in any one of the preceding claims wherein the reaction is carried out at reflux temperature.

8. A process as claimed in any one of the preceding claims wherein the aniline compound is 4-(2,2-dichloro-1,1 -difluoroethoxy)aniline.

9. A process as claimed in any one of the preceding claims wherein the aniline is prepared by reacting a phenol compound having the formula:

wherein R and R' are as defined in claim 1 with a haloethane, haloethylene, halobenzene or a halopyridine.

10. A process as claimed in claim 9 wherein the reaction is carried out in a polar solvent in the presence of an alkali metal base.

11. A process as claimed in claim 10 wherein the reaction is carried out at a temperature in the range of from -5 0 to 25 C.

1 2. A process as claimed in any one of claims 9 to 11 wherein the haloethylene is 1,1-dichloro2,2-difluoroethylene.

1 3. A process as claimed in claim 1 substantially as hereinbefore described with reference to any one of the Examples.

14. A benzoylphenylurea whenever prepared by a process as claimed in any one of the preceding claims.