JPS6048965A - 3-methyl-4-difluoromethyl-delta2-1,2,4-triazolen-5-one and its preparation - Google Patents

Abstract

NEW MATERIAL:A 3-methyl-4-difluoromethyl-DELTA<2>-1,2,4-triazolin-5-one shown by the formula I (R is lower alkyl, or propergyl). EXAMPLE:1-( 3-Propargyloxyphenyl )-3-methyl-4-difluoromethyl-DELTA<2>-1, 2, 4-triazolin- 5-one. USE:An intermediate for synthesizing a compound useful as an agricultural chemical, especially a herbicide. PREPARATION:1-( 3-Hydroxyphenyl )-3-methyl-4-difluoromethyl-DELTA<2>-1,2,4-triazolin- 5-one shown by the formula II is reacted with a compound shown by the formula III (X is halogen) in an inert solvent in the presence of a base such as K2CO3, etc. at 40-150 deg.C for 1-6hr, to give a compound shown by the formula I .

Description

Detailed Description of the Invention The present invention provides 6-methyl-4-difluoromethyl-Δ2 represented by the general formula (IJ (in the formula, R represents a lower alkyl group or a propargyl group))
-1.2.4-triazolin-5-ones and 1-(S-hydroxyphenyl)-5-methyl-4-difluoromethyl-Δ2-12.4-)riasilyl/ -5-one is reacted with a compound represented by the general formula (III) R4 (wherein R represents a lower alkyl group or a propargyl group, and X represents a halogen atom). (Regarding the method for producing the compound represented by 11.

The compounds of the present invention are novel compounds that have not been described in the literature and are important intermediates for the production of compounds useful as pesticides, especially herbicides. The present invention also provides a method for producing the compound represented by formula (1).

For example, the manufacturing method of the present invention can be diagrammatically expressed as follows.

(1) (1) (However, in the formula, R and X have the same meanings as above.) That is, 1-(6-hydroxyphenyl)-3-methyl-4-difluoromethyl- Δ
”-1,2,4-) riazolin-5-one and general formula (B
3-Methyl-4-difluoromethyl-7112-1,2,4- represented by the general formula (1) by reacting with the compound represented by the formula (1) in an inert solvent in the presence of a base.
) riazolin-5-ones can be obtained.

Inert solvents that can be used in the present invention include aromatic hydrocarbons such as benzene, toluene, and xylene; methanol and ethanol, as long as they do not significantly inhibit this type of reaction.

Alcohols such as prohanol and glycol; ethers such as diethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, and cyclohexanone; lower fatty acid esters such as ethyl acetate; lower aliphatic amides such as dimethylformamide and dimethylacetamide , water, dimethyl sulfoxide and the like.

These solvents can be used alone or in mixtures.

Examples of bases that can be used in the reaction of the present invention include sodium carbonate, sodium hydride, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, potassium hydroxide, potassium hydroxide, and alkali metals. Examples include inorganic bases such as alcolade, and organic bases such as pyridine, trimethylamine, triethylamine, diethylaniline, and 1,8-diazabicyclo-(5,4,O]-7-undecene.

Phase transfer catalysts such as triethylbenzylammonium chloride can also be used.

The reaction of the present invention is carried out under heating, and the reaction temperature is 40 to 1
The temperature is appropriately selected from the range of 50°C. Further, the reaction time is selected from the range of 1 to 6 hours.

Since the reaction of the present invention is an equimolar reaction, it is carried out using equimolar amounts of each reaction component, but one of the components may be used in excess.

After completion of the reaction, the desired compound represented by the formula (υ) can be obtained by processing according to a conventional method.

1-(5-hydroxyphenyl)-6-methyl-4-difluoromethyl-Δ2-triazolin-5-one represented by the structural formula (In) can be synthesized, for example, by the method illustrated below.

(IX) (■ (branch) (V) (IV) (However, in the formula, R represents a lower alkyl group, and 2 represents a halogen atom.) Hydrazine represented by the structural formula (■) and the general formula (■ ) in an inert solvent under heating to form a 1-(3-nitrophenyl)-3-methyl-Δ2-1゜2.4-) liazoline represented by the structural formula (■). −
5-one, and the compound represented by the formula (■) is reacted with the compound represented by the general formula (W) in an inert solvent to obtain 1-(5-nitrophenyl)- represented by the structural formula (■).
6-Methyl-4-difluoromethyl-Δ2-1.2.4
1-(3-aminophenyl)-3-methyl-4- by reducing this compound (■) in the presence of a reducing agent.
Difluoromethyl-Δ2-1.2.4-triazoline-
5-one, and this compound (fV) is diazotized and then thermally decomposed to obtain 1 represented by the structural formula (II).
-(5-Hydroxyphenyl>-5-Mef-4-difluorome-f-to-Δ2-1.2.4-)Ryazoline-
5-one can be obtained.

Representative examples of the compounds of the present invention are shown in Table 1 below, but the present invention is not limited thereto.

Table 1 Some examples of the present invention are shown below.

Example 1 l-(5-hydroxyphenyl)-3-meth-4-
difluoromethyl-Δ2-1.2.4-) liazolin-5-one 28.5f (0.12 mol), propargyl bromide 14.39 (α 12 mol), charcoal ffipotassium 16.5f (α 12 mol) and acetone 150 ml of the mixture is reacted for 4 hours under reflux. After the reaction is completed, the reaction solution is cooled, the precipitated salt is removed by filtration, and the solvent is distilled off from the solution f to obtain crystals. By recrystallizing the obtained crystals from isobrophenol,
L! Is' 1-(3-propargyloxyphenyl)
-3-Methyl-4-difluoromethyl-Δ2-1.2.
4-) Riazolin-5-one is obtained.

Melting point: 99-101°C Yield: 91.8% Example 2 l-(5-hydroxyphenyl)-2-methyl-4-difluoromethyl-Δ! -1,2,4-) riazoline-5
-one 24.0SF (α1 mol) and sodium hydroxide 4.29 (0.1 mol) were dissolved in ethanol 150 resistant, and this solution was added to propargyl chloride a2f (1 mol) at room temperature.
, 11 mol) and the reaction was carried out under reflux for 4 hours. After the reaction is completed, the reaction solution is cooled, water is added, the precipitated crystals are collected by filtration, and re-crystallized from inglobanol.
1.87 1-(5-propargyloxyphenyl)
-3-Methyl-4-difluoromethyl-Δ2-1゜2.
4-triazolin-5-one is obtained.

Example 3 l-(3-hydroxyphenyl)-5-methyl-4-difluoromethyl-Δ2-1.2.4-triazoline-5
-one 2a5S' (112 mol), inpropylbromide 1tay (o, 12 mol), potassium carbonate 1tsy
A mixture of (α12 mol) and 15011 Il of acetone is reacted for 4 hours under reflux.

After the reaction is completed, the reaction solution is cooled, the precipitated salt is separated by f, and f
By distilling off the solvent from the solution, 1-(3
-inpropoxyphenyl)=3-methyl-4-difluoromethyl-Δ2-1°2.4-triazolin-5-one 19.6S' is obtained.

Yield 6αl NMRacDCIs 1.4~ts (d, 6H), z,
4s (S, 3H) MS 4.5-4.8 (m, IH) 6.05-7.98
(t, IH) 6.6-6.85 (m, IH)
7.1-7.5 (m, 3H) Patent applicant Nihon Nohyaku Co., Ltd. 518-

Claims (2)

[Claims] (1) 3-methyl-4-difluoromethyl-Δ2 represented by general formula (I): (wherein R represents a lower alkyl group or a propargyl group)
-1.2.4-) Riazolin-5-ones. (2) Structural formula (■): The general formula (110: General formula (1) characterized by reacting a compound represented by the formula %() (wherein R represents a lower alkyl group or a propargyl group, and X represents a halogen atom) (however, the formula R represents the same meaning as above; 3-methyl-4-difluoromethyl-Δ!-1,2,
4-,) Method for producing riazolin-5-ones.