IE73669B1 - Process for the preparation of aminotriazine derivatives - Google Patents
Process for the preparation of aminotriazine derivativesInfo
- Publication number
- IE73669B1 IE73669B1 IE411390A IE411390A IE73669B1 IE 73669 B1 IE73669 B1 IE 73669B1 IE 411390 A IE411390 A IE 411390A IE 411390 A IE411390 A IE 411390A IE 73669 B1 IE73669 B1 IE 73669B1
- Authority
- IE
- Ireland
- Prior art keywords
- formula
- compound
- phenyl
- preparation
- alkyl
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D253/00—Heterocyclic compounds containing six-membered rings having three nitrogen atoms as the only ring hetero atoms, not provided for by group C07D251/00
- C07D253/02—Heterocyclic compounds containing six-membered rings having three nitrogen atoms as the only ring hetero atoms, not provided for by group C07D251/00 not condensed with other rings
- C07D253/06—1,2,4-Triazines
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D271/00—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms
- C07D271/02—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms not condensed with other rings
- C07D271/10—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D271/00—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms
- C07D271/02—Heterocyclic compounds containing five-membered rings having two nitrogen atoms and one oxygen atom as the only ring hetero atoms not condensed with other rings
- C07D271/10—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles
- C07D271/113—1,3,4-Oxadiazoles; Hydrogenated 1,3,4-oxadiazoles with oxygen, sulfur or nitrogen atoms, directly attached to ring carbon atoms, the nitrogen atoms not forming part of a nitro radical
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D401/00—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom
- C07D401/02—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings
- C07D401/12—Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, at least one ring being a six-membered ring with only one nitrogen atom containing two hetero rings linked by a chain containing hetero atoms as chain links
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D413/00—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms
- C07D413/02—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms containing two hetero rings
- C07D413/06—Heterocyclic compounds containing two or more hetero rings, at least one ring having nitrogen and oxygen atoms as the only ring hetero atoms containing two hetero rings linked by a carbon chain containing only aliphatic carbon atoms
Abstract
Method for the preparation of aminotriazine derivatives of the formula in which R is hydrogen, C1-C6-alkyl, C3-C6-cycloalkyl, C1-C4-alkyl which is substituted by 1 to 10 halogen atoms or 1 to 3 radicals from the group comprising C1-C3-alkoxy, C1-C3-alkylthio or phenyl, or is phenyl, or phenyl which is substituted by 1 to 3 radicals from the group comprising halogen, methyl, ethyl, methoxy, methylthio or nitro, characterised in that a compound of the formula II in which R1 is hydrogen, C1-C4-alkyl, C2-C6-cycloalkyl, C1-C4-alkyl which is substituted by 1 to 9 chlorine atoms, C1-C3-alkoxy, C1-C3-alkylthio, C1-C3-alkylsulphinyl, C1-C3-alkylsulphonyl, phenyl, phenyl which is substituted by 1 to 3 radicals from the group comprising halogen, methyl, ethyl, methoxy, methylthio or nitro, or pyridyl, is reacted with hydrazine hydrate, and the resulting compound of the formula III is subjected to acid hydrolysis. The compounds prepared according to the invention are suitable as starting materials for the preparation of effective pesticides.
Description
The present invention relates to a novel process for the preparation of 4-amino-3-oxo-2,3,4,5-tetrahydro-l,2,4triazines.
The invention relates to a process for the preparation of a 5 compound of formula I
H wherein R is hydrogen, C!-C6alkyl, C3-C6cycloalkyl, Cj-C,alkyl substituted by one or more halogen atoms or by from 1 to 3 radicals from the group C1-C3alkoxy, Cj-C3alkylthio and phenyl, phenyl or phenyl substituted by from 1 to 3 radicals from the group halogen, methyl, ethyl, methoxy, methylthio and nitro, which process comprises reacting with hydrazine hydrate a compound of formula II
o wherein Rj is hydrogen, Cj-C^alkyl, C3-C6cycloalkyl, Cj-C,,alkyl substituted by from 1 to 9 chlorine atoms, Cj-C3alkoxy,
Ci-C3alkylthio, Cj-C3alkylsulfinyl, Cx-C3alkylsulfonyl, phenyl, phenyl substituted by from 1 to 3 radicals from the group halogen, methyl, ethyl, methoxy, methylthio and nitro, or pyridyl, and
R is as defined above; and subjecting the resulting compound of formula III
Η to hydrolysis, preferably acid hydrolysis.
The present process is preferably used for the preparation of compounds of formula I wherein R is methyl, ethyl, isopropyl, tert-butyl or cyclopropyl. The process is preferably carried out using compounds of formula II wherein Rj is Ci-C^alkyl as starting materials.
The aminotriazine derivatives of formula I prepared according to the invention can be used as intermediates for the preparation of 4—[(pyrid-3-yl)-methyleneamino]- or 4-[(pyrid-3yl)-methylamino]-3-oxo-2,3,4,5-tetrahydro-l,2,4-triazines, which are distinguished by pronounced insecticidal and acaricidal activity. Such pesticidal compounds are, for example,
4-[(pyrid-3-yl)-methyleneamino]-3-oxo-6-methyl-2,3,4,5tetrahydro-1,2,4-triazine, 4-[(pyrid-3-y1)-methyleneamino]3- oxo-6-cyclopropyl-2,3,4,5-tetrahydro-l,2,4-triazine,
4— [(pyrid-3-yl)-methylamino]-3-oxo-6-isopropyl-2,3,4,5-tetrahydro-l , 2 , 4-triazine and 4-[(pyrid-3-yl)-methylamino]-3-oxo6-tert-butyl-2,3,4,5-tetrahydro-l,2,4-triazine. Such pesticidal compounds, their preparation and use are described in EP Patent Application 314 615.
The process according to the invention can be illustrated by the following reaction scheme, the radicals R and Rj being as defined above:
' 20
The first step (ring expansion) of the process according to the invention for the preparation of the compounds of formula I is usually carried out under normal pressure and preferably in a solvent. The temperature is from +15 to
120°C, preferably from +20 to 100°C. Suitable solvents are, for example, water, nitriles, such as acetonitrile, alcohols, dioxane or tetrahydrofuran. The subsequent hydrolysis of the acylamino compounds of formula III to the free amino compounds of formula I is preferably carried out with inor10 ganic acids, such as IN hydrochloric acid to cone, hydrochloric acid or IN to ION sulfuric acid, at temperatures of from 0 to 120°C, especially from +20 to 100'C, in an aqueous medium or in organic solvents, such as alcohols, dioxane, tetrahydrofuran or nitriles.
The 1,3,4-oxadiazolin-2-on-3-yl-ketones of formula II used as starting materials according to the invention are novel.
They can be prepared analogously to known procedures, for example as follows (see, for example, EP Patent Application No. 314 615):
u
II
X -CH2-C -R -II (V)
In the above formulae IV and V, R and R, are as defined above and X is a halogen atom, preferably chlorine or bromine. The above process for the preparation of the oxadiazolinone ketones of formula II is generally carried out under normal pressure in the presence of a base and in a solvent. The temperature is from 0 to +150 °C, preferably from +20 to 100°C. Suitable bases are organic and inorganic bases, for example trimethylamine, alcoholates, sodium hydroxide or sodium hydride. Suitable solvents are, inter alia. alcohols, halogenated hydrocarbons, for example chloroform, nitriles, for example acetonitrile, tetrahydrofuran, dioxane, dimethyl sulfoxide, dimethylformamide or water.
The oxadiazolinones of formula IV [see EP Patent Application No. 321 833; J. Pharm. Soc. Japan 76 . 1300-1303 (1956);
Vol. 82., 121-123 (1949)] and their preparation, - and also the haloketones of formula V, are for the most part known.
It is known from Liebigs Ann. Chem. 749. 125 ff. (1971) that 4-amino-6-phenyl-3-oxo-2,3,4,5-tetrahydro-l,2,4-triazines can be obtained starting from 2-amino-5-methyl-3-phenacyl-l,3,4oxadiazolium bromide by reaction with hydrazine hydrate. The main disadvantage of this process is that it is limited to the preparation of 1,2,4-triazine rings that are phenylsubstituted in the 6-position; in addition, this process comprises several steps and its yield is poor. Furthermore, it is known from EP Patent Application No. 314 615 to prepare
4- amino-3-oxo-2,3,4,5-tetrahydro-l,2,4-triazines that are substituted in the 6-position, by reacting corresponding
- trifluoromethyl-1,3,4-oxadiazolin-2-on-3-yl-ketones with excess hydrazine in a one-step reaction:
wherein A may be an unsubstituted or substituted alkyl or aryl substituent. The disadvantages of this process are primarily the high cost of the trifluoroacetic acid ethyl ester required for preparing the trifluoroacethydrazide, the instability of that trifluoroacethydrazide at room temperature, and the not very high yield in the reaction of the trifluoroacethydrazide with phosgene in water (see Helv.
Chim. Acta 1986. 333) to prepare the 5-trifluoromethyl1.3.4- oxadiazol-2(3H)-one from which the 5-trifluoromethyl1.3.4- oxadiazolin-2-on-3-yl-ketones of formula Ila above (starting compound) are obtained. Moreover, the reaction according to EP Patent Application No. 314 615 inevitably produces toxic trifluoroacetic acid derivatives as a byproduct, which present ecological problems and require a considerable outlay for their disposal.
In contrast, within the scope of the present invention it has now surprisingly been found that the presence of a 5-CF3 group in the starting compounds of formula II is not necessary for the preparation of the 4-amino-3-oxo-2,3,4,5-tetrahydro-l,2,4-triazines of formula I by ring expansion. The present starting compounds of formula II, which contain one of the mentioned radicals Rx in the 5-position instead of the mentioned CF3 group, react readily with hydrazine hydrate to form the acylamino compounds of formula III, from which, however, the radical -CO-Rj must subsequently be removed by acid hydrolysis to obtain the compounds of formula I. With r>'·' the process according to the invention, the disadvantages of < the procedures hitherto available are eliminated since, in the process according to the invention, inexpensive and j readily available starting compounds can be used, high yields are obtained and, instead of toxic trifluoroacetic acid derivatives, ecologically harmless carboxylic acid derivatives, for example acetic acid, are formed as a by-product.
The compounds of the formula
H wherein R and Rj are as defined in claim 1, with the proviso that in compounds of formula III wherein R is phenyl, Rj is other than methyl, n-butyl and phenyl, are novel, and the present invention relates also to them.
Example 1: Preparation of the starting compound
2,3-Dihydro-5-methyl-2-oxo-l.3.4-oxadiazole-3-acetone
g of 2,3-dihydro-5-methyl-2-oxo-l,3,4-oxadiazole (prepared in customary manner from acethydrazide and phosgene) are added to a solution of 2.3 g of sodium in 100 ml of methanol, the mixture is stirred for a short time and then the solvent is removed in vacuo at a bath temperature of 60°C. The sodium salt so formed is introduced in portions into a solution of 9.2 g of chloroacetone and 0.2 g of tetrabutylammonium bromide in 50 ml of chloroform, and the reaction mixture is stirred for 4 hours at 65°C. After the salts have been filtered off, the solvent is removed in vacuo at a bath temperature of 50°C. The residue that remains is recrystallised from tert-butyl methyl ether, yielding the title ► compound having a melting point of 55-57°C.
f
The following compounds of formula II are also prepared in a 5 manner corresponding to that described above:
phys.
b.p.
(0.08
m.p.
D.p.
(0.07
m.p.
m.p.
m.p.
m.p.
m.p.
m.p.
data
0.104 mbar torr)/80’C
55-58°C
0.091 mbar torr)/102°C
179-181’C
98-102’C
126-129°C .116-118’C
164-168’C
146-148’C
Example 2:
a) Preparation of 4-acetylamino-6-methyl-3-oxo-2,3.4.5- » tetrahvdro-1,2,4-triazine (ring expansion):
ι
3.12 g of the 2,3-dihydro-5-methyl-2-oxo-l,3,4-oxadiazole5 3-acetone prepared according to Example- 1 are stirred in ml of alcohol together with 2 g of hydrazine hydrate for 16 hours at a bath temperature of 35 °C. After the solvent and the excess hydrazine have been evaporated off in vacuo. recrystallisation from isopropanol yields the title compound having a melting point of 197-199°C.
The following compounds of formula III are also prepared in a manner corresponding to that described above:
R
H
-CH,
-C(CH3)3
-CH
-CH
-CH
-CH
-CH
-CH.
-CH.
-CH.
-CH
-CH.
-CF
m.p. [°C]
185-187°
197-199°
205-207°
252-255°
255-257°
228-231°
259-262°
259-262°
b) Preparation of 4-amino-6-methyl-3-oxo-2.3.4.5-tetrahvdro1.2,4-triazine (acid hydrolysis):
1.7 g of the 4-acetylamino-6-methyl-3-oxo-2,3,4,5-tetrahydro-l ,2,4-triazine prepared according to a) above are stirred for 5 hours in 10 ml of 2N hydrochloric acid at 80°C. After cooling of the solution, 1.7 g of sodium acetate are added and the solution is concentrated by evaporation in a rotary evaporator at a bath temperature of 60°C. The residue formed is stirred with ethanol and freed of salt precipitates by filtration. The resulting solution is concentrated to a small volume and caused to crystallise. The title compound is obtained in the form of colourless crystals having a melting point of 116-119°C.
The following compounds of formula I are also prepared in a manner corresponding to that described above:
-ch3
-C2H5
-C3H7(i)
-C(CH3)3
-n
m.p. [°C]
116-119°
143-145°
79- 81°
148-150°
94- 95°
199-202°
208-210°
Claims (11)
1. A process for the preparation of a compound of formula I H wherein R is hydrogen, C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl, C)-C d alkyl substituted by one or more halogen atoms or by from 1 to 3 radicals from the group Cj-C^alkoxy, C,-C 3 alkylthio and phenyl, phenyl or phenyl substituted by from 1 to 3 radicals from the group halogen, methyl, ethyl, methoxy, methylthio and nitro, which process comprises reacting with hydrazine hydrate a compound of formula II o wherein Rj is hydrogen, Cj-C^alkyl, C 3 -C 6 cycloalkyl, Ci-C 4 15 alkyl substituted by from 1 to 9 chlorine atoms, Cj-C^alkoxy, Ci—C 3 alkylthio, C t -C 3 alkylsulfinyl, Ci-C 3 alkylsulfonyl, phenyl, phenyl substituted by from 1 to 3 radicals from the group halogen, methyl, ethyl, methoxy, methylthio and nitro, or pyridyl; and *20 R is as defined above; and subjecting the resulting compound of formula III Η Η R Ο Η Ν -ΝΗ-CO-R (III) to hydrolysis.
2. A process according to claim 1, wherein the compound of formula III is subjected to acid hydrolysis.
3. A process according to claim 1 or 2, wherein the compound of formula III is subjected to hydrolysis with an inorganic acid.
4. A process according to any one of claims 1 to 3 for the preparation of a compound of formula I wherein R is methyl, ethyl, isopropyl, tert-butyl or cyclopropyl.
5. A process according to any one of claims Ito 4, wherein a compound of formula II wherein Rj is C 1 -C 4 alkyl is reacted.
6. A compound of the formula N R N -CH 2 -CO-R (II) wherein R and R, are as defined in claim 1.
7. A compound of the formula NH-CO-R H (III) wherein R and Rj are as defined in claim 1, with the proviso that in compounds of formula III wherein R is phenyl, R t is other than methyl, n-butyl and phenyl.
8. A process according to claim 1 for the preparation of a 5 compound of formula I given and defined therein, substantially as hereinbefore described and exemplified.
9. A compound of formula I given and defined in claim 1, whenever prepared by a process claimed in a preceding claim.
10. A compound of formula II as claimed in claim 6, substantially 10 as hereinbefore described and exemplified.
11. A compound of formula III as claimed in claim 7, substantially as hereinbefore described and exemplified.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH410789 | 1989-11-15 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| IE904113A1 IE904113A1 (en) | 1991-05-22 |
| IE73669B1 true IE73669B1 (en) | 1997-07-02 |
Family
ID=4269949
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IE411390A IE73669B1 (en) | 1989-11-15 | 1990-11-14 | Process for the preparation of aminotriazine derivatives |
Country Status (14)
| Country | Link |
|---|---|
| EP (1) | EP0433218B1 (en) |
| JP (1) | JP2943010B2 (en) |
| KR (1) | KR0150208B1 (en) |
| CA (2) | CA2320676C (en) |
| DE (1) | DE59010496D1 (en) |
| DK (1) | DK0433218T3 (en) |
| ES (1) | ES2091815T3 (en) |
| GR (1) | GR3020992T3 (en) |
| IE (1) | IE73669B1 (en) |
| IL (3) | IL111617A (en) |
| PT (1) | PT95888B (en) |
| SG (1) | SG43813A1 (en) |
| TW (1) | TW199149B (en) |
| ZA (1) | ZA909120B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9304178D0 (en) * | 1993-03-02 | 1993-04-21 | Ciba Geigy Ag | Process for the preparation of 6-alkyl-4-(pyridin-3-yl-methyleneamino),5-dihydro-1,2,4-triazin-3(2h)-one |
| US5384403A (en) * | 1993-03-31 | 1995-01-24 | Ciba-Geigy Corporation | Process for the preparation of aminotriazine derivatives |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5416515B1 (en) * | 1968-08-19 | 1979-06-22 | ||
| JPS6011478A (en) * | 1983-06-30 | 1985-01-21 | Showa Denko Kk | Oxadiazolinon derivative and herbicide |
| US4699647A (en) * | 1985-05-30 | 1987-10-13 | E. I. Du Pont De Nemours And Company | Herbicidal sulfonamides |
| DE3853662D1 (en) * | 1987-10-16 | 1995-06-01 | Ciba Geigy Ag | Pesticides. |
-
1990
- 1990-10-24 TW TW079108994A patent/TW199149B/zh active
- 1990-11-06 EP EP90810853A patent/EP0433218B1/en not_active Expired - Lifetime
- 1990-11-06 DE DE59010496T patent/DE59010496D1/en not_active Expired - Lifetime
- 1990-11-06 ES ES90810853T patent/ES2091815T3/en not_active Expired - Lifetime
- 1990-11-06 DK DK90810853.3T patent/DK0433218T3/en not_active Application Discontinuation
- 1990-11-06 SG SG1996001138A patent/SG43813A1/en unknown
- 1990-11-08 IL IL11161790A patent/IL111617A/en not_active IP Right Cessation
- 1990-11-08 IL IL9628090A patent/IL96280A/en not_active IP Right Cessation
- 1990-11-13 CA CA002320676A patent/CA2320676C/en not_active Expired - Lifetime
- 1990-11-13 CA CA002029838A patent/CA2029838C/en not_active Expired - Lifetime
- 1990-11-14 KR KR1019900018447A patent/KR0150208B1/en not_active IP Right Cessation
- 1990-11-14 PT PT95888A patent/PT95888B/en not_active IP Right Cessation
- 1990-11-14 IE IE411390A patent/IE73669B1/en not_active IP Right Cessation
- 1990-11-14 ZA ZA909120A patent/ZA909120B/en unknown
- 1990-11-15 JP JP2310158A patent/JP2943010B2/en not_active Expired - Lifetime
-
1994
- 1994-11-14 IL IL11161794A patent/IL111617A0/en unknown
-
1996
- 1996-09-12 GR GR960402339T patent/GR3020992T3/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| KR0150208B1 (en) | 1998-10-15 |
| PT95888A (en) | 1991-09-13 |
| IL111617A0 (en) | 1995-01-24 |
| IL96280A0 (en) | 1991-08-16 |
| DE59010496D1 (en) | 1996-10-17 |
| PT95888B (en) | 1997-11-28 |
| ZA909120B (en) | 1991-07-31 |
| CA2029838C (en) | 2001-06-19 |
| IE904113A1 (en) | 1991-05-22 |
| EP0433218B1 (en) | 1996-09-11 |
| ES2091815T3 (en) | 1996-11-16 |
| CA2029838A1 (en) | 1991-05-16 |
| DK0433218T3 (en) | 1996-09-30 |
| TW199149B (en) | 1993-02-01 |
| CA2320676A1 (en) | 1991-05-16 |
| EP0433218A1 (en) | 1991-06-19 |
| IL111617A (en) | 1996-05-14 |
| KR910009677A (en) | 1991-06-28 |
| SG43813A1 (en) | 1997-11-14 |
| JPH03188070A (en) | 1991-08-16 |
| JP2943010B2 (en) | 1999-08-30 |
| IL96280A (en) | 1996-01-31 |
| GR3020992T3 (en) | 1996-12-31 |
| CA2320676C (en) | 2004-11-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MK9A | Patent expired |