GB2073736A - Process for Preparing Pyridinyloxyphenoxy Compounds and Derivatives Thereof - Google Patents
Process for Preparing Pyridinyloxyphenoxy Compounds and Derivatives Thereof Download PDFInfo
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- GB2073736A GB2073736A GB8025185A GB8025185A GB2073736A GB 2073736 A GB2073736 A GB 2073736A GB 8025185 A GB8025185 A GB 8025185A GB 8025185 A GB8025185 A GB 8025185A GB 2073736 A GB2073736 A GB 2073736A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic 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
- C07D213/02—Heterocyclic 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
- C07D213/04—Heterocyclic 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
- C07D213/60—Heterocyclic 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
- C07D213/62—Oxygen or sulfur atoms
- C07D213/63—One oxygen atom
- C07D213/64—One oxygen atom attached in position 2 or 6
- C07D213/643—2-Phenoxypyridines; Derivatives thereof
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
- A01N43/34—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one nitrogen atom as the only ring hetero atom
- A01N43/40—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one nitrogen atom as the only ring hetero atom six-membered rings
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- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical & Material Sciences (AREA)
- Dentistry (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Plant Pathology (AREA)
- General Health & Medical Sciences (AREA)
- Wood Science & Technology (AREA)
- Zoology (AREA)
- Environmental Sciences (AREA)
- Pest Control & Pesticides (AREA)
- Agronomy & Crop Science (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Pyridine Compounds (AREA)
Abstract
Herbicidal (substituted pyridin-2- yloxy)phenoxy-propionate or -valerate derivatives are prepared by reacting a 4-(substituted pyridin-2-yloxy)- phenol with an appropriate diazo-propionate or -valerate, derivative; by reacting the diazo- propionate or -valerate derivative with one phenolic group of hydroquinone, the other phenolic group then being reacted with the appropriately substituted 2-halopyridine; or by reacting the diazo-propionate or -valerate derivative with a phenol carrying a group which is easily convertible into, or replaceable by, an appropriately substituted pyridin-2- yloxy group, followed by the conversion or replacement step. Also the novel diazo-propionate and -valerate derivatives and a method for their preparation.
Description
SPECIFICATION
Process for Preparing Pyridinyloxyphenoxy Compounds and Derivatives Thereof
This invention relates to a process for preparing pyridyloxyphenoxy compounds and their derivatives, and to intermediates useful in the process. The compounds are valuable herbicides.
According to the present invention there is provided a process for the preparation of compounds having the general formula (I):
wherein each of Z and Y, which may be the same or different, is hydrogen, fluorine, chlorine bromine, iodine, trifluoromethyl, difluoromethyl or chlorodifluoromethyl, provided that at least one of Z and Y is trifluoromethyl, difluoromethyl or chlorodifluoromethyl;R' represents hydrogen or an alkyl radical of 1 to 4 carbon atoms; and R2 is a cyano group; a carboxyl group; a carbonamido group
wherein R3 is hydrogen or an alkyl radical and R4 is hydrogen, an optionally hydroxy or phenyl-substituted alkyl radical of 1 to 4 carbon atoms, a phenyl or chlorophenyl radical, an alkoxy radical of 1 to 4 carbon atoms, or a group -NR5R8 wherein R5 is hydrogen or alkyl of 1 to 4 carbon atoms, and R6 is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl or chlorophenyl, or the groupNR3R4 constitutes a pyrrolidino, piperidino, or morpholino radical; a group
wherein R7 is alkyl or phenyl; an alkoxycarbonyl group wherein the alkoxy group may be straight or branched, and which optionally bears one or more hydroxy, alkoxy, or halogen substituents, or bears a substituent of Formula (I) wherein R2 represents a
radical; a group
wherein R8 is an alkyl radical of 1 to 4 carbon atoms and m is an integer from 1 to 5 inclusive; a cyclohexyloxycarbonyl radical optionally substituted by one or more halogen atoms or methyl radicals; an alkenyloxycarbonyl radical in which the alkenyl group contains from 3 to 6 carbon atoms; a phenoxycarbonyl radical optionally bearing one or more halogen or methyl substituents; or a benzyloxycarbonyl radical, the phenyl group of which optionally bears one or more halogen or methyl substituents; n is O or 2, which comprises reacting a compound of general formula (it):
wherein Y and Z have the meanings defined above, with a diazo compound of the formula (III): R'CNz(CH2)nR2 (III) wherein R1, R2 and n have the previously defined meanings, in the presence of a catalyst.
Examples of the catalysts which may be used in the above process are metallic copper e.g. in the form of copper powder or copper bronze, and rhodium compounds such as RhCI3. 3H20, Rh[P(C6H5)3]3 and Rh(O . COR)4 in which R is an alkyl or an aryl radical.
The reaction may also be catalysed by the action of ultraviolet radiation.
Compounds of general formulae (I) and (II) wherein n is 0 and details of certain methods for their preparation are disclosed in European Patent Application No. 0001473.
Compounds of formula (III), which are novel compounds, and as such constitute a further feature of the present invention, may be obtained by the action of nitrous acid on the appropriate amine having the formula (IV):
wherein R1, R2 and n have the previously defined meanings. From what follows it will be apprecated by those skilled in the art that several of the groups R2 as hereinbefore defined may enter into complicating or modifying side reactions, for example when R2 is a hydroxyl containing entity. In these instances the desired (I) may still be obtained by the simple expedient of, for example, an appropriate protection-deprotection sequence being inserted into the process or by an additional reaction or reactions to restore the modified functional group to its intended state.
A particularly convenient and useful series of compounds (IV) in the present instance are the esters of (DI) ala nine. Since the chiral centre in such compounds is destroyed on conversion to the diazo esters (III) there is nothing to be gained by using the more expensive resolved alanines.
The conversion of (IV) into (Ill) may be carried out, typically, by mixing a solution in water of the hydrochloride of (IV) with an inert solvent, for example, 1 ,2-dichloroethane, benzene, dichloromethane or ethyleneglycol dimethyl ether, cooling the mixture to OOC and then under an atmosphere of nitrogen and with vigorous stirring, an ice-cold aqueous solution of sodium nitrite is added. The mixture is then gradually treated at OOC with 5% wlw aqueous sulphuric acid solution and finally the phases are allowed to separate.The organic layer is well washed with 5% aqueous sodium bicarbonate solution and dried over anhydrous sodium sulphate, all these operations being carried out at OOC. The solution of the diazo compound in the organic solvent is then ready for use.
The reaction of the compound of formula (II) with the diazo compound (III) is carried out in the presence of a catalyst, for example, rhodium acetate Rh2(OCOCH3)4. Typically, as concentrated a solution of (II) as feasible is prepared in the same organic solvent as was used in the preparation of the diazo compound solution. The catalyst is added in amount from 0.02 to 0.0001 mol. conveniently from 0.004 to 0.0005 mol, per mol of diazo compound, and the solution of diazo compound is then added slowly (to minimise the formation of dimers) with rapid stirring at room temperature. Progress of the reaction is followed by measuring the evolution of nitrogen.A small excess of the compound of formula (It) is employed to ensure complete consumption of the diazo compound (III). The compound of formula (I) may then be isolated from the reaction mixture by conventional means.
In an alternative synthesis of the compounds of formula (I) the diazo compound (Ill) is first reacted with hydroquinone to give a compound of formula:
which is subsequently reacted with a compound of formula:
wherein Y and Z have the previously defined meanings and X is halogen (e.g. fluorine, chlorine or bromine).
Compounds of formula (VI) are old compounds which can be prepared by methods known in the art;
When carrying out the above alternative process it is preferred to use an excess of hydroquinone over the diazo compound (III) in order to minimise the formation of the bis-ether of formula:
The reaction between hydroquinone and the diazo ester (III) is carried out under similar conditions to those described above for the reaction between (II) and (III).
The reaction of the compound of general formula (V) with the compound of general formula (VI) to give the compound of general formula (I) is suitably performed in the presence of a dry base and a solvent or diluent. Examples of suitable solvents are lower alkyl ketones, for example, methyl ethyl ketone. The reaction may be accelerated by heating and may, for example, be conveniently carried out at the reflux temperature of the solvent. Examples of suitable bases are inorganic bases such as sodium or potassium carbonate. If desired, a mixture of a compound of general formula (VI) wherein X is chlorine with a compound wherein X is fluorine can be used.
In a yet further alternative synethesis of the compounds of general formula (I) the diazo compound (III) is first reacted with a phenol of the formula:
to give a compound of the formula:
In the above process W is a group which is inert to the diazo compound and which is readily convertible into, or replaceable by, the group of formula:
wherein Y and Z have the previously defined meanings.
The reaction between the diazo compound (III) and the phenol of formula (VII) is carried out under similar conditions to those described above for the reaction between (II) and (III), using a slight excess of the phenol over the diazo compound.
Compounds of formula (I) which are of particular value are those in which Z is CF3, Y is hydrogen, RX is methyl, n is 0 and R2 is an alkoxycarbonyl radical in which the alkoxy group contains from 1 to 6 carbon atoms.
The invention is further illustrated by the following Example in which the parts and percentages are by weight unless otherwise indicated.
Example (i) Preparation of a Solution of n-Butyl-a-diazopropionate: CH3 . CN2 . CO2Bu" A solution of 3.63 parts of n-butylamine hydrochloride in 5 parts of water was mixed with 12.2 parts of 1 2-dichloroethane; this mixture was stirred vigorously under nitrogen at -50C and to it was added dropwise 6.66 parts of a cold solution of sodium nitrite (1.66 parts) in water (5 parts). The mixture was stirred for a further 10 minutes and then 2 parts of a 5% w/v sulphuric acid solution were added during 1 0 minutes.After another 10 minute period of stirring, the organic layer was separated, washed with 5% aqueous sodium bicarbonate solution (3x60 parts) and dried (Na2SO4); the whole procedure was carried out at approximately OOC. The resulting solution of diazopropionate was stored overnight in a refrigerator before use.
(ii) Preparation of n-Butyl-a-[4-(5'-trifluoromethylpyridyl-2'-oxy)phenoxy] propionate:
A mixture of 10.2 parts of 4-(5-trifluoromethylpyridyl-2-oxy)-phenol, 24.4 parts of 1,2dichloromethane and 0.05 parts of Rh2(OAc)4 . 2MeOH was stirred at room temperature in a flask connected to a gas burette. The diazo ester solution prepared above was then added during 10 hours and the progress of the reaction monitored by evolution of N2. The reaction mixture was heated at reflux for 1 hour and the presence of the desired product was confirmed by gas chromatographic and mass spectrometric analysis.
Claims (14)
1. A process for the preparation of compounds having the general formula (I):
wherein each of Z and Y, which may be the same or different, is hydrogen, fluorine, chlorine bromine, iodine, trifluoromethyl, difluoromethyl or chlorodifluoromethyl, provided that at least one of Z and Y is trifluoromethyl, difluoromethyl or chlorodifluoromethyl;R' represents hydrogen or an alkyl radical of 1 to 4 carbon atoms; and R2 is a cyano group; a carboxyl group; a carbonamido group
wherein R3 is hydrogen or an alkyl radical and R4 is hydrogen, an optionally hydroxy or phenylsubstituted alkyl radical of 1 to 4 carbon atoms, a phenyl or chlorophenyl radical, an alkoxy radical of 1 to 4 carbon atoms, or a group ~NR5RB wherein R5 is hydrogen or alkyl of 1 to 4 carbon atoms, and RH is hydrogen, alkyl of 1 to 4 carbon atoms, phenyl or chlorophenyl, or the group -NR3R4 constitutes a pyrrolidino, piperidino, or morpholino radical; a group
wherein R7 is alkyl or phenyl; an alkoxycarbonyl group wherein the alkoxy group may be straight or branched, and which optionally bears one or more hydroxy, alkoxy, or halogen substituents, or bears a substituent of Formula (I) wherein R2 represents a
radical; a group
wherein R8 is an alkyl radical of 1 to 4 carbon atoms and m is an integer from 1 to 5 inclusive; a cyclohexylcarbonyl radical optionally substituted by one or more halogen atoms or methyl radicals; an alkenyloxycarbonyl radical in which the alkenyl group contains from 3 to 6 carbon atoms; a phenoxycarbonyl radical optionally bearing one or more halogen or methyl substituents, or a benzyloxycarbonyl radical, the phenyl group of which optionally bears one or more halogen or methyl substituents; n is 0 or 2, which comprises reacting a compound of general formula (ill):
wherein Y and Z have the meanings defined above, with a diazo compound of the formula (III): R'CN2(CH2)nR2 (III) wherein R1, R2 and n have the previously defined meanings in the presence of a catalyst.
2. A process as claimed in claim 1 wherein the catalyst is rhodium acetate.
3. A process as claimed in claim 1 or claim 2 wherein the catalyst is used in an amount from 0.02 to 0.0001 mol per mol of the diazo compound.
4. A process as claimed in claim 1 or claim 2 wherein the catalyst is used as an amount from 0.004 to 0.0005 mol per mol of the diazo compound.
5. A process as claimed in claim 1, substantially as hereinbefore described in the foregoing
Example.
6. A process for the preparation of compounds having the general formula (I) as defined in claim 1 which comprises reacting a diazo compound of the formula R'CN2(CH2)nR2 (ill) wherein R, R and n have the meanings defined in claim 1, with hydroquinone to give a compound having the formula:
which is subsequently reacted with a compound of formula:
wherein Y and Z have the meanings defined in claim 1 and X is halogen.
7. A process for the preparation of compounds having the general formula (I) as defined in claim 1 which comprises reacting a diazo compound of the formula: R'CN2(CH2)nR2 wherein R1, R2 and n have the meanings defined in claim 1, with a phenol of the formula:
to give a compound of the formula:
wherein W is a group which is inert to the diazo compound and which is readily convertible into, or replaceable by, the group of formula:
wherein Y and Z have the meanings defined in claim 1, followed by the said conversion or replacement of the group Win the compound of formula (VIII).
8. A compound having the general formula (I) as defined in claim 1, whenever obtained by a process as claimed in any one of the preceding claims.
9. Diazo compounds of the formula: R'CN2(CH2)nR2 wherein R1, R2 and n have the meanings defined in claim 1.
10. Diazo compounds as claimed in claim 1, substantially as hereinbefore described in the foregoing Example.
11. A process for the preparation of the diazo compounds claimed in claim 9 which comprises reacting an amine of the formula:
wherein R1, R2 and n have the meanings defined in claim 1, with nitrous acid.
12. A process as claimed in claim 11 wherein the amine of formula:
is an ester of (DL)alanine.
13. A process as claimed in claim 11 substantially as hereinbefore described in the foregoing
Example.
14. Diazo compounds as claimed in claim 9 whenever obtained by a process as claimed in any one of claims 11 to 13.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8025185A GB2073736B (en) | 1979-10-03 | 1980-08-01 | Process for preparing pyridinyloxyphenoxy compounds and derivatives thereof |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB7934327 | 1979-10-03 | ||
| GB8025185A GB2073736B (en) | 1979-10-03 | 1980-08-01 | Process for preparing pyridinyloxyphenoxy compounds and derivatives thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2073736A true GB2073736A (en) | 1981-10-21 |
| GB2073736B GB2073736B (en) | 1984-02-01 |
Family
ID=26273087
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8025185A Expired GB2073736B (en) | 1979-10-03 | 1980-08-01 | Process for preparing pyridinyloxyphenoxy compounds and derivatives thereof |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2073736B (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0136593A2 (en) * | 1983-09-06 | 1985-04-10 | The Dow Chemical Company | Novel halopyridines and methods of making |
| US4931457A (en) * | 1989-06-28 | 1990-06-05 | Hoechst-Roussel Pharmaceuticals Inc. | Naphthylamino-and naphthyloxy-pyridinamine comounds useful as topical antiinflammatory agents for the treatment of skin disorders |
| US4959378A (en) * | 1989-10-24 | 1990-09-25 | Hoechst-Roussel Pharmaceuticals Inc. | Aminopyridinylaminophenol compounds useful as topical antiinflammatory agents for the treatment of skin disorders |
| US4959377A (en) * | 1989-06-29 | 1990-09-25 | Hoechst-Roussel Pharmaceuticals Inc. | Phenoxypyridinamine compounds which are use as a dermatological composition |
| US4970219A (en) * | 1989-06-28 | 1990-11-13 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino- and heteroaryloxypyridinamine compounds which have useful utility in treating skin disorders |
| US4983615A (en) * | 1989-06-28 | 1991-01-08 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino- and heteroaryloxypyridinamine compounds which are useful in treating skin disorders |
| US4992448A (en) * | 1989-10-24 | 1991-02-12 | Hoechst-Roussel Pharmaceuticals Inc. | Benzocycloalkylaminopyridinamines and related compounds as topical antiinflammatory agents for the treatment of skin disorders |
| US5034403A (en) * | 1989-06-28 | 1991-07-23 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino-and heteroaryloxypyridinamines and related compounds |
-
1980
- 1980-08-01 GB GB8025185A patent/GB2073736B/en not_active Expired
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0136593A2 (en) * | 1983-09-06 | 1985-04-10 | The Dow Chemical Company | Novel halopyridines and methods of making |
| EP0136593A3 (en) * | 1983-09-06 | 1988-03-30 | The Dow Chemical Company | Novel halopyridines and methods of making |
| US4931457A (en) * | 1989-06-28 | 1990-06-05 | Hoechst-Roussel Pharmaceuticals Inc. | Naphthylamino-and naphthyloxy-pyridinamine comounds useful as topical antiinflammatory agents for the treatment of skin disorders |
| US4970219A (en) * | 1989-06-28 | 1990-11-13 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino- and heteroaryloxypyridinamine compounds which have useful utility in treating skin disorders |
| US4983615A (en) * | 1989-06-28 | 1991-01-08 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino- and heteroaryloxypyridinamine compounds which are useful in treating skin disorders |
| US5034403A (en) * | 1989-06-28 | 1991-07-23 | Hoechst-Roussel Pharmaceuticals Inc. | Heteroarylamino-and heteroaryloxypyridinamines and related compounds |
| US4959377A (en) * | 1989-06-29 | 1990-09-25 | Hoechst-Roussel Pharmaceuticals Inc. | Phenoxypyridinamine compounds which are use as a dermatological composition |
| US4959378A (en) * | 1989-10-24 | 1990-09-25 | Hoechst-Roussel Pharmaceuticals Inc. | Aminopyridinylaminophenol compounds useful as topical antiinflammatory agents for the treatment of skin disorders |
| US4992448A (en) * | 1989-10-24 | 1991-02-12 | Hoechst-Roussel Pharmaceuticals Inc. | Benzocycloalkylaminopyridinamines and related compounds as topical antiinflammatory agents for the treatment of skin disorders |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2073736B (en) | 1984-02-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19920801 |