JPH0635460B2 - 2-Piperazinopyrimidine derivative - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel 2-piperazinopyrimidine derivative useful as a herbicide.

[Conventional technology]

A compound in which a ring containing nitrogen or carbonyl is condensed with a pyrimidine ring, for example, as a compound having a pyridopyrimidine structure, Chemical Abstracts (Chem, Abst.) 90 Vol 54893
(1979), 97, 182350 (1982). However, there are structural differences in size from the compounds of the present invention, and the usefulness of these known compounds for agricultural applications has not been clarified at all.

[Outline of Invention]

The present invention has the general formula [I] [In the formula, R ¹ is hydrogen or an aralkyl group, R ² is an alkyl group having 5 or more carbon atoms, a cycloalkyl group, a hydroxyl group-substituted lower alkyl group, a lower alkoxy group-substituted lower alkyl group,
A di-lower alkylamino group-substituted lower alkyl group or aralkyl group. ] It is related with the 2-piperazino pyrimidine derivative represented by this.

[Substance of the present application]

The substance of the present application is represented by the general formula [I], and as the aralkyl group of R ^{1 in} the formula, a benzyl group, a diphenylmethyl group, a triphenylmethyl group and the like can be mentioned, and a benzyl group is particularly preferable. preferable.

The alkyl group of R ² has 5 or more carbon atoms, and includes, for example, amyl groups such as n-amyl group, hexyl groups such as n-hexyl group, heptyl groups such as n-heptyl group, and n- Examples thereof include octyl groups such as octyl group, and n-heptyl group is particularly preferable. The cycloalkyl group represented by R ² is preferably a cycloalkyl group having 4 to 7 carbon atoms, particularly a cyclohexyl group having 6 carbon atoms. Examples of the hydroxyl-substituted lower alkyl group for R ² include, for example, a methylol group and an ethylol group, and the latter is preferable, and the lower alkoxy-substituted lower alkyl group for R ² has 1 to 8 carbon atoms. Examples thereof include a methoxymethyl group, an ethoxymethyl group, a methoxyethyl group, an ethoxyethyl group, and the like. Among them, a methoxyethyl group is preferable, and as the di-lower alkylamino group-substituted lower alkyl group for R ² , , For example, 2-dimethylaminoethyl group, 2-
Diethylaminoethyl group. Of these, preferably the former, the aralkyl group R ² in addition to those exemplified in R ^1, may be mentioned a 2-phenylethyl group, among others benzyl, 2-phenylethyl It is preferably a group.

Further, the substance of the present application may be in a free state or in a salt form, for example, an acid addition salt form. Such salts can also be used as herbicides. Examples of the acid addition salt include mineral acids such as hydrochloric acid, sulfuric acid and phosphoric acid, and organic acids such as acetic acid, maleic acid and citric acid.

Hereinafter, among the substances of the present application, particularly preferable ones will be exemplified.

[Production Method] The substance of the present invention represented by the general formula [I] can be produced according to the following reaction formula. The case where R ¹ is a benzyl group will be described as an example.

The compound can be synthesized, for example, by the reference example described later. Compound with a reaction solvent such as water, methanol, ethanol, THF or DMF at 0 to 100 ° C.
React for 0.5 to 10 hours. The compound can be synthesized by reacting the compound with an amine having a group corresponding to R ² . The compound can be obtained by reacting the starting compound in a reaction solvent such as water, alcohols, THF, DMF, toluene and xylene at 0 to 150 ° C. for 0.5 to 20 hours.

Furthermore, the compound in which R ¹ is hydrogen can be obtained by hydrogenolysis of a compound corresponding to the compound.
As the hydrocracking catalyst, Pd-C, Raney-Ni, Pt-C,
PdO or the like is used. The reaction solvent is methanol, ethanol, alcohol such as isopropanol, formic acid, acetic acid,
Use carboxylic acid such as propionic acid, mixed solvent such as ethanol-formic acid, ethanol-acetic acid, etc. under normal pressure or
Supply hydrogen at 10kg / cm ² , 0.1 to 10 at 10 to 100 ℃
React for hours. After the reaction, the target compound can be obtained by a conventional method.

〔Usefulness〕

The substance of the present invention has excellent activity as a herbicide. That is, the substance of the present application can be used as a paddy field and upland herbicide. The weeds to be used as herbicides are particularly effective against paddy field weeds such as Taenia japonicus, Pleurotus cornucopia, Kokonagi, Firefly, Hera modada, etc., and field weeds such as Hie, Mehibushiba, Oinutade, Aoyu, Kogomekaya and Shiraza.

In order to use the substance of the present invention as a herbicide, the substance of the present invention alone or in combination with a carrier, a surfactant, a dispersant, an auxiliary agent or the like is formulated into a wettable powder, an emulsion, a fine granule or a granule, and the like. Dilute to different concentration and spray or apply directly.

Hereinafter, the present invention will be specifically described with reference to Examples and the like.

[Examples, etc.]

Reference Example 4-chloromethyl-2- (4-benzylpiperazino) pyrimidine-5-carboxylic acid ethyl ester 1-amidino-4-benzylpiperazine sulfate 9.7 g (3
6.4 mmol) and THF 185 ml, to a suspension of 1.5 g of NaOH 15 ml of H ₂ O
Add the solution dissolved in to neutralize.

Then, a solution of 8 g (36.4 mmol) of ethyl 4-chloro-2-ethoxymethylene-acetoacetate in 200 ml of THF was added to 20 ml.
After the dropping, the mixture is stirred at the same temperature for 1 hour. After completion of stirring, 300 ml of ether was added and washed with water three times. The organic layer was dried over anhydrous MgSO ₄ and the solvent was distilled off under reduced pressure to obtain 11.8 g of the pale yellow target product. (Yield 86.7%) ¹ H-NMR spectrum (CDCl ₃ solvent, δppm) 1.37 (3H, t, J = 7Hz), 2.51 (4H, t, J = 6Hz), 3.75 (2H, S),
3.97 (4H, t, J = 6Hz), 4.34 (2H, q, J = 7Hz), 4.88 (2H, s),
7.32 (5H, s). Example 1 2- (4-benzylpiperazino) -6-cyclohexyl-5-oxo-5,6-dihydro (7H) pyrrolo [3,4-d] pyrimidine 2- (4-benzylpiperazino) -4-chloromethylpyrimidine-5-carboxylic acid ethyl ester 2.0 g (5.34 m
mol) was dissolved in 40 ml of isoamyl alcohol, 10.5 g (107 mmol) of cyclohexylamine was added, and the mixture was refluxed for 6 hours. After completion of the reaction, the solvent was distilled off, The residue was washed with ether to give 1.32g of the title compound as crystals (yield 63%) mp 176-178 ° C. IR absorption spectrum (CHCl ₃ solution, cm ^{- 1)} 3120,2850,2800,1670,1610,1572,1350,1005. ^{1 H-NMR} spectrum (CDCl ₃ solution, δppm) 1.20-2.00 (10H), 2.52 (4H, t, J = 5Hz), 3.58 ( 2H, s), 3.9
6 (4H, t, J = 5Hz), 4.18 (2H, s), 7.37 (5H, s), 8.69 (1H,
s). The compounds of Table 1 were obtained by the same method.

Example 7 6-Cyclohexyl-5-oxo-2-piperazino-5,6-dihydro (7H) pyrrolo [3,4-
d] pyrimidine 2- (4-benzylpiperazino) -6-cyclohexyl-5-oxo-5,6-dihydro (7H) pyrrolo [3,3
1.2 g (3.07 mmol, Example 1) of 4-d] pyrimidine was dissolved in 30 ml of ethanol, 0.16 g of 10% Pd-C was added, and hydrogenolysis was performed at 60 ° C. After completion of the reaction, Pd-C was passed and ethanol was distilled off to obtain 0.92 g of the title compound as crystals (yield-100%).

Melting point 177-180 ° C Infrared absorption spectrum (CHCl ₃ solution, cm ^-1 ) 3330,2920,2850,1670,1610,1570,1345,978. ¹ H-NMR spectrum (CDCl ₃ solution, δppm) 1.20-2.00 ( 10H), 2.94 (4H, t, J = 5Hz), 3.92 (4H, t, J = 5H
z), 4.19 (2H, s), 8.69 (1H, s). The compounds in Table 2 were obtained by the same method.

Claims (1)

[Claims] 1. A general formula [I] [In the formula, R ¹ is hydrogen or an aralkyl group, R ² is an alkyl group having 5 or more carbon atoms, a cycloalkyl group, a hydroxyl group-substituted lower alkyl group, a lower alkoxy group-substituted lower alkyl group,
A di-lower alkylamino group-substituted lower alkyl group or aralkyl group. ] The 2-piperazino pyrimidine derivative represented by these.