CA1215357A - Process for the preparation of aryloxybenzoic acids containing a sulphonamide group - Google Patents

Process for the preparation of aryloxybenzoic acids containing a sulphonamide group

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Publication number
CA1215357A
CA1215357A CA000447470A CA447470A CA1215357A CA 1215357 A CA1215357 A CA 1215357A CA 000447470 A CA000447470 A CA 000447470A CA 447470 A CA447470 A CA 447470A CA 1215357 A CA1215357 A CA 1215357A
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Canada
Prior art keywords
process according
general formula
group
carbon atoms
alkyl
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
CA000447470A
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French (fr)
Inventor
Alain Chene
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Bayer CropScience SA
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Rhone Poulenc Agrochimie SA
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D213/00Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
    • C07D213/02Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
    • C07D213/04Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D213/60Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D213/62Oxygen or sulfur atoms
    • C07D213/63One oxygen atom
    • C07D213/64One oxygen atom attached in position 2 or 6
    • C07D213/6432-Phenoxypyridines; Derivatives thereof
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C303/00Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
    • C07C303/36Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of amides of sulfonic acids
    • C07C303/40Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of amides of sulfonic acids by reactions not involving the formation of sulfonamide groups

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Pyridine Compounds (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

ABSTRACT
"PROCESS FOR THE PREPARATION OF ARYLOXYBENZOIC ACIDS
CONTAINING A SULPHONAMIDE GROUP"
Process for the preparation of an N-sulphonyl-aryloxy benzamide by reacting an aryloxybenzoic acid with a sulphonyl isocyanate or isothiocyanate.

Description

~2~S;~57 DESCRIPTION

PROCESS FOR THE PREPARATION OF ARYLOXYBENZOIC ACIDS
_ CONTAINING A SULPHONAMIDE GROUP _ _ _ The present invention relates to an improved process for the preparation of certain aryloxybenzoic acid derivatives containing a sulphonamide group and having herbicidal properties.
Herbicidal derivatives of aryloxybenzoic acids containing a sulphonamide group (or N-sulphonyl-phenoxy-benzamides) are known from European Patent Applications 3,416 and 23,392 and Japanese Patent Application No.
82.106,654.
These patent applications disclose many compounds of this type, in particular compounds of the general formula:

zl z CO-NH-SO -R3 D~ ~ ~ A (I) E W
and salts thereof, wherein A is hydrogen, fluorine, 15 chlorine, bromine, iodine or a nitro group; -N=NCF3; N2; a dialkylamino group; an alkyl group; trialkylammonio;
alkylthio, alkylsulphinyl, alkylsulphonyl, dialkylsulphonio, cyanosulphonyl, alkanoyloxy, alkoxy, alkoxy which is substituted by alkoxycarbonyl, nitroso, -SCN, azide, CF3, 20 -N=N-~-(OCH3)2 or acyl; Z is hydrogen, fluorine, chlorine, o :~2~S~5~7 bromine, iodine or an alkyl, alkoxy, alk~lsulphinyl, alkylsulphonyl, CF3, N02 or CN group; ~ is hydrogen or halogen, or an alkyl or dialkylamino group, D is fluorine, chlorine, bromine or iodine, or a CF3, alkylthio, 5 alkylsulphinyl, alkylsulphonyl, halogenoalkyl, sulphamyl, formyl, alkylcarbonyl, C~ or dimethylami~o group; E is hydrogen or a halogenoalkyl, alkoxy, alkylsulphinyl, alkylsulphonyl, CN or CF3 group, W is a trivalent nitrogen atom or a -C(G)=group; G has one of the meanings given for 10 Z, and R3 is a phenyl, pyridyl or thienyl group which is optionally substituted by one or more halogen atoms, alkyl groups or nitro groups, or is an alkenyl or alkynyl radical of 2 to 4 carbon atoms or an alkyl radical of 1 to 4 carbon atoms, which are optionally substituted by one or more 15 fluorine, chlorine, bromine or iodine atoms, preferably CF3, or by one or more of the following substituents: alkoxycar-bonyl of 2 to 5 carbon atoms, alkylcarbonyl of 2 to 5 carbon atoms, dialkylcarbamyl in which the alkyl groups have from 1 to 4 carbon atoms, alkylthio, alkylsulphinyl or alkyl-20 sulphonyl, each having 1 to 4 carbon atoms, alkylcarbony-loxy of 2 to 5 carbon atoms or cyano.
In this spécification and the accompanying claims, alkyl groups and moieties, unless otherwise specified, are straight or branched-chain and preferably contain from 1 to 25 4 carbon atoms.
According to the known processes, the compounds of lZ~i35'7 general formula (I~ CaQ be prepared by reacting an intermediate acid halide of the formula:

zl z COX

D ~ 0 ~ (II) E
5 wherein X is chlorine, bromine or iodine and A, z, zl, D, E and W are as hereinbefore defined, with a sulphonamide of the general formula:

R S2N~2 (III) wherein R3 is as hereinbefore defined, at between 25 and 10 140C, generally in the presence of an acid acceptor, in particular a tertiary amine, such as N,N-dimethylaniline or pyridine, or an alkali metal carbonate, such as anhydrous potassium carbonate or an alkali metal fluoride such as cesium fluoride.
The compounds of general formula (I) can then be alkylated in a known manner, for example by reaction with a diazoalkane having 1 to 4 carbon atoms, in a manner such that the corresponding products substituted by an alkyl group of 1 to 4 carbon atoms on the nitrogen atom of the 20 sulphonamide group are obtained, the hydrogen atom of this same nitrogen atom may also be replaced by alkali mPtal atoms, such as sodium, for example by the action of a basic alkaline agent to give alkali metal salts of ccmpounds of general formula (I).

12:1S;~S7 This known process for condensation of compounds of the general formulae (II) and (III) has various disadvantages, in particular mediocre yields. It is believed that it is generally the presence of an acid 5 acceptor which decreases the yield since it promotes the diacylation reaction. Moreover, the use of an acid acceptor renders isolation and purification of the final products more difficult and more expensive.
Another disadvantage of the known process is that 10 a supplementary reaction stage is necessary to obtain the acid halide of general formula (II) starting from the acid of general formula (IV) defined hereinafter.
An object of the present invention is to overcome the disadvantages of the known processes. Other 15 advantages will appear in the course of the description which follows.
The present invention provides a process for the preparation of a compound of general formula (I) wherein the various symbols are as hereinbefore defined which 20 comprises reacting an acid of the general formula:

zl z COOH
~ ~ (IV) D ~ ~ ~ O ~ A
E~W

with a sulphonyl isocyanate or isothiocyanate of the general formula:

3 Z~5357 R S02-N=C-Y (V) wherein Y is an oxygen or sulphur atom and the s~mbols A, Z, Z , D E, W, and R3 are as hereinbefore defined. This process is in general effected in the liquid phase, 5 preferably in the presence of a catalyst, and at a temperature such that the compound COY (that is to say carbon dioxide, if Y - 0, or carbonyl sulphide, if Y = S) which forms during the reaction is eliminated from the reaction mixture progressively, in gaseous form.
A sub-group of compounds of general formula (I) which are particularly appropriately and advantageously prepared by the process according to the present invention comprises the compounds of general formula (I) wherein A
is a hydrogen atom, an N02 group or a chlorine atom; Z is 15 a halogen atom, more especially chlorine; zl and E are hydrogen atoms, D is the CF3 group, R3 is an alkyl group, preferably having 1 to 4 carbon atoms, especially CH3, and W is -CH=, and more especially 5-[2'-chloro-4'-(trifluoromethyl)-phenoxy~-2-nitro-N-methanesulphonyl-20 benzamide.
The preferred reactants of general formulae (IV)and (V) are chosen in such a way that the symbols present in their formulae have meanings corresponding to those given hereinbefore for the compounds of general formula 25 (I).
Of the catalysts which can be used, there may be ~Z~3S~

mentioned non-limitatively: tertiary amines, such as triethylamine, pyridine, N,~-dimethylaniline or 1,4-di-azabicyclo(2,2,2) octane, or tin derivatives, in particular alkyl-tin salts, such as dibutyl-tin diacetate 5 or dibutyl-tin dilaurate. Tertiary amines and alkyl-tin salts are preferred.
The molar ratio Df the compound of general formula (IV) to the compound of general formula ~V) is generally between 0.8:1 and 1.2:1, preferably between 0.9:1 and 10 1.1:1; more especially these reagents are used in stoichiometric proportions.
The molar ratio of catalyst to acid of general formula (IV) in general varies between 0.001:1 and 0.1:1, and is preferably between 0.01:1 and 0.05:1.
The reagents are preferably dissolved in an inert aprotic organic solvent having a boiling point greater than or equal to the reaction temperature, for example an aliphatic or aromatic, chlorinated or non-chlorinated liquid hydrocarbon, such as benzene, toluene, the xylenes, 20 xylene mixtures, 1,2-dichloroethane or chlorobenzene, or an ether or nitrile: it is also possible to use a mixture of several solvents. The use of an inert solvent has the practical advantage of allowing better transfer of heat in a process carried out on an industrial scale: it also 25 enables local overheating of the reaction mixture to be avoided.

~s~

As hereinbefore indicated, t~e temperature at which the process according to the present invention is carried out is advantageously such that the compound of the formula COY (carbon dioxide or carbonyl sulphide) formed in the 5 course of the reaction is eliminated f~om the reaction mixture in gaseous form progressively as it is generated.
Moreover, this temperature is lower than the decomposition temperature of the compounds of general formulae (IV), (V) and (I) i-nvolved in the process. In the case where a 10 solvent is used, the reaction temperature is advantageously less than or equal to the boiling point of the solvent and is generally between 60 and 180C and preferably between 70 and 150C.
At the end of the reaction, the compound of general 15 formula (I) can be isolated by methods ~nown ~ se. By the term "methods kno~n per se" as used in the present specification is meant methods herQtofore used or described in the chemical literature.
The process according to the present invention is 20 distinguished by the simplicity of the method of recovery of the end product, since this product is generally insoluble in the hot reaction mixture and separates out as crystals in a pure form, so that this recovery is essentially reduced to filtration. This filtration can 25 also be facilîtated by addition of a non-solvent.
The following non-limitative examples illustrate ~Z~L5357 the present invention.
Example 1 5 g (0.0138 mol) of 5-[2'-chloro-4'-(trifluoromethyl)-phenoxy]-2-nitrobenzoic acid are 5 suspended in 10 cm3 of toluene. The suspension is stirred and 1.9 g tO.0138 mol) of methanesulphonyl isothiocyanate and 0.04 g (0.0004 mol) of triethylamime are added at room temperature~ The reaction mixture is heated, with stirring and while boiling under reflux, for 10 minutes.
10 Carbonyl sulphide escapes from the reaction mixture progressively as it is formed. After addition of 20 cm3 of toluene, the precipitate formed is filtered off and washed with toluene and then with methylene chloride.
5 g (0.0114 mol, 83% yield) of a white solid 15 consisting of 5-~2'-chloro-4'-(trifluoromethyl)-phenoxy]-
2-nitro-N-methanesulphonylbenzamide of melting point 218C
are thus obtained. The structure of this product is confirmed by infra-red and nuclear magnetic resonance spectroscopy.
Example 2 Proceeding as described in Example 1 but replacing the 1.9 g of methanesulphonyl isothiocyanate by 1,7 g of methanesulphonyl isocyanate (CH3S02N=C=0), 5-[2'-chloro-4'-(trifluoromethyl)-phenoxy]-2-nitro-~-25 methanesulphonylbenzamide is obtained in a yield of 88%.

Claims (18)

The embodiment of the invention, in which an exclusive privilege or property is claimed, are defined as follows:
1. A process for the preparation of a compound of the general formula:

wherein A is hydrogen, fluorine, chlorine, bromine, iodine or a nitro group; -N=NCF3: N?; a dialkylamino group; an alkyl group; trialkylammonio;
alkylthio, alkylsulphinyl, alkylsulphonyl, dialkyl-sulphonio, cyanosulphonyl, alkanoyloxy, alkoxy, alkoxy which is substituted by alkoxycarbonyl, nitroso, -SCN, azide, CF3, -N=N-?-(OCH3)2 or acyl; Z is hydrogen, fluorine, chlorine, bromine, iodine or an alkyl, alkoxy, alkylsulphinyl, alkylsulphonyl, CF3, NO2 or CN group; Z1 is hydrogen or halogen, or an alkyl or dialkylamino group, D is fluorine, chlorine, bromine or iodine, or a CF3, alkylthio, alkylsulphinyl, alkylsulphonyl, halogenoalkyl, sulphamyl, formyl, alkylcarbonyl, CN or dimethylamino group; E is hydrogen or a halogenoalkyl, alkoxy, alkylsulphinyl, alkylsulphonyl, CN or CF3 group; W is a trivalent nitrogen atom or a -C(G)= group; G has one of the meanings given for Z; and R3 is a phenyl, pyridyl or thienyl group which is optionally substituted by one or more halogen atoms, alkyl groups or nitro groups, or is an alkenyl or alkynyl radical having 2 to 4 carbon atoms or an alkyl radical of 1 to 4 carbon atoms, which are optionally substituted by one or more fluorine, chlorine, bromine or iodine atoms, or by one or more of the following substituents: alkoxycarbonyl of 2 to 5 carbon atoms, alkylcarbonyl of 2 to 5 carbon atoms, dialkylcarbamyl in which the alkyl groups have from 1 to 4 carbon atoms, alkylthio, alkylsulphinyl or alkylsulphonyl, each having 1 to 4 carbon atoms, alkylcarbonyloxy of 2 to 5 carbon atoms or cyano, which comprises reacting an acid of the general formula:

(IV) with a sulphonyl isocyanate or isothiocyanate of the general formula:

R3SO2-N=C=Y (V) wherein Y is an oxygen or sulphur atom and the symbols A, Z, Z1, D, E, W and R3 are as hereinbefore defined.
2. A process according to claim 1 wherein R2 represents CF3.
3. A process according to claim 1 or 2, wherein the reaction is carried out in the liquid phase at a temperature such that the compound COY formed during the reaction is eliminated from the reaction mixture progressively, in gaseous form.
4. A process according to claim 1, wherein the reaction is carried out in the presence of a catalyst.
5. A process according to claim 4 wherein the catalyst is a tertiary amine or an alkyl-tin salt.
6. A process according to claim 4 or 5 wherein the molar ratio of catalyst to acid of general formula (IV) is between 0.001:1 and 0.1:1.
7. A process according to claim 4 or 5 wherein the molar ration of catalyst to acid of general formula (IV) is between 0.01:1 and 0.05:1.
8. A process according to claim 1 wherein the molar ration of acid of general formula (IV) to sulphonyl isocyanate or isothiocyanate of general formula (V) is between 0.8:1 and 1.2:1.
9. a process according to claim 1 wherein the molar ratio of acid of general formula (IV) to sulphonyl isocyanate or isothiocyanate of general formula (V) is between 0.9:1 and 1.1:1.
10. A process according to claim 1 wherein the acid of general formula (IV) and the sulphonyl isocyanate or isothiocyanate of general formula (V) are used in stoichiometric proportions.
11. A process according to claim 1 wherein the reaction is carried out in an inert aprotic organic solvent having a boiling point greater than or equal to the reaction temperature.
12. A process according to claim 11 wherein the solvent is an aliphatic or aromatic liquid hydrocarbon or an ether or nitrile.
13. A process according to claim 11 or 12 wherein the reaction temperature is less than or equal to the boiling point of the solvent.
14. A process according to claim 11 or 12 wherein the reaction temperature is between 60 and 180°C.
15. A process according to claim 11 or 12 wherein the reaction temperature is between 70 and 150°C.
16. A process according to claim 1 wherein in general formula (I), (IV) and (V) depicted in claim 1, A is a hydrogen or chlorine atom or an NO2 group, Z is a halogen atom, Z' and E are hydrogen atoms, D is CF3, R3 is an alkyl group and W is -CH=.
17. A process according to claim 16 wherein R3 is an alkyl group having 1 to 4 carbon atoms.
18. A process according to claim 16 wherein R3 is CH3.
CA000447470A 1983-02-17 1984-02-15 Process for the preparation of aryloxybenzoic acids containing a sulphonamide group Expired CA1215357A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR83/02806 1983-02-17
FR8302806A FR2541274A1 (en) 1983-02-17 1983-02-17 PROCESS FOR THE PREPARATION OF SULFONAMIDE GROUP PHENOXYBENZOIC ACIDS

Publications (1)

Publication Number Publication Date
CA1215357A true CA1215357A (en) 1986-12-16

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ID=9286128

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CA000447470A Expired CA1215357A (en) 1983-02-17 1984-02-15 Process for the preparation of aryloxybenzoic acids containing a sulphonamide group

Country Status (19)

Country Link
JP (1) JPS59193865A (en)
KR (1) KR850001161A (en)
BE (1) BE898929A (en)
BR (1) BR8400639A (en)
CA (1) CA1215357A (en)
CH (1) CH658860A5 (en)
DE (1) DE3405589A1 (en)
DK (1) DK71884A (en)
ES (1) ES8501375A1 (en)
FR (1) FR2541274A1 (en)
GB (1) GB2135309B (en)
IL (1) IL70981A (en)
IT (1) IT1173247B (en)
LU (1) LU85214A1 (en)
NL (1) NL8400370A (en)
PT (1) PT78121B (en)
RO (1) RO88473A (en)
SE (1) SE8400886L (en)
ZA (1) ZA841121B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9930369D0 (en) * 1999-12-22 2000-02-09 Zeneca Ltd Chemical process

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE830507C (en) * 1950-02-14 1952-02-04 Basf Ag Process for the preparation of acylated sulfamides
EP0003416B1 (en) * 1978-01-19 1981-08-26 Imperial Chemical Industries Plc Diphenyl ether compounds useful as herbicides; methods of using them, processes for preparing them, and herbicidal compositions containing them
FR2510106A1 (en) * 1981-07-27 1983-01-28 Rhone Poulenc Agrochimie HERBICIDE COMPOUNDS DERIVED FROM PHENOXYBENZOIC ACIDS, AND METHODS FOR THEIR PREPARATION AND USE
FR2510104A1 (en) * 1981-07-27 1983-01-28 Rhone Poulenc Agrochimie HERBICIDE COMPOUNDS DERIVED FROM PHENOXYBENZOIC ACIDS

Also Published As

Publication number Publication date
ES529783A0 (en) 1984-11-16
FR2541274B1 (en) 1985-03-22
IL70981A0 (en) 1984-05-31
BR8400639A (en) 1984-09-25
PT78121B (en) 1986-07-17
GB8403962D0 (en) 1984-03-21
IL70981A (en) 1987-01-30
LU85214A1 (en) 1985-09-12
NL8400370A (en) 1984-09-17
JPS59193865A (en) 1984-11-02
SE8400886L (en) 1984-08-18
IT1173247B (en) 1987-06-18
IT8419480A0 (en) 1984-02-07
GB2135309A (en) 1984-08-30
GB2135309B (en) 1986-04-23
ES8501375A1 (en) 1984-11-16
DE3405589A1 (en) 1984-08-23
DK71884A (en) 1984-08-18
ZA841121B (en) 1984-09-26
DK71884D0 (en) 1984-02-16
FR2541274A1 (en) 1984-08-24
RO88473A (en) 1986-01-30
PT78121A (en) 1984-03-01
CH658860A5 (en) 1986-12-15
KR850001161A (en) 1985-03-16
SE8400886D0 (en) 1984-02-17
BE898929A (en) 1984-08-16

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