JPS5910568A - 2-bromo-6-methylaminopyridine and its preparation - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to 2-bromo-6-methylaminopyridine and a method for producing the same.

2-Bromo-6-methylaminopyridine is a compound useful as an intermediate for structural medicine, agricultural chemicals, and the like.

The 2-bromo-6-methylaminopyridine of the present invention is produced by reacting it with sodium methoxide to give 2-methoxy-6-methylaminopyridine, which is then reacted with 2-naphthylylolthioformate to produce 0-2- Naphthyl N-(6
-Medoxy 2-pyridyl)-N-methylthiocarbamate can be produced.

Regarding the usefulness of the herbicide containing 0-2-naphthyl N-(6-medoxy-2-pyridyl)-N-methylthiocarbamate as an active ingredient, Japanese Patent Application No. 57-0
It is disclosed in the specification of No. 40759, and exhibits extremely excellent herbicidal activity against many weeds including field weeds, and is harmless to transplanted paddy rice, making it suitable as a paddy field herbicide.

'It still shows an excellent selective weeding effect between grass weeds and broad-leaved crops when treated with upland soil, and has applicability as a herbicide for upland fields.

The 2-bromo-6-methylaminopyridine of the present invention is 2.
Reaction of 6-dibromopyridine with methylamine, reaction of 2-amino-6-bromopyridine with methyl iodide or dimethyl sulfate, or acetylation of Fi2-amino-6-bromopyridine followed by methylation to produce 2-acetyl-6 -Bromo-2-methylpyridi/binding, followed by hydrolysis reaction, etc. can be produced by a method known in the art.

The present invention (h) provides a method for producing 2-bromo-6-methylaminopyridine, which is characterized by reacting 2,6-dibromopyridine with methylamine.

Methylamine has a ratio of about 2 to 2,6-dibromopyridine.
It is used in an amount of more than twice the molar amount, preferably about 2 to about 10 times the molar amount. It is preferable to use a solvent to facilitate the reaction. Examples of the solvent include 2,6-dibromopyridine, water that does not react with methylamine and dissolves methylamine, benzene, and alcohol.

Methylamine is a gas at room temperature and is usually available as an aqueous solution. Therefore, it is generally convenient to react Z6-dibromopyridine with an aqueous methylamine solution.

The reaction is usually carried out at a temperature of about 60 to about 180°C, preferably about 90 to about 120°C. The reaction time is closely related to the reaction temperature, but generally about 3 to about 8 hours is sufficient.

EXAMPLES Next, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 20C1ml), Q) 60- of an aqueous solution of 2,6-dipromoviridine 259,404-methylamine was placed in a magnetic stirring autoclave and reacted at 110°C for 5 hours.

After the reaction was completed, the autoclave was cooled, the contents were taken out, and the solid obtained by filtration was recrystallized from n-hexane to obtain 2-bromo-6-methylaminopyridine 199 having a melting point of 63 to 64°C.

Infrared absorption spectrum (KBr) 3520<-NH>, 2930(c-H>, 1590,
144o, 1410 ((Q) cm → Nuclear magnetic resonance absorption spectrum (aDat3. Internal standard TMS) δ 2
．． 90(d) ppm 3 Hδ 5.30
'l IHδ &23(d)
II IHδ &67(d)'/
11 (δ 7.22 (t) V 111 elemental analysis value (0, as IH7Br horse) OHN
Br analysis value (@S&56 3.85 14.88 4
2.91 Gunron value (→ 5B, 55 5.77 14.
97 42.720C! -Molecular weight by Mass 18
6 Example 2 Into the same reaction apparatus as in Example 1, 60 me of a 40% methylamine aqueous solution of 2,6-dipromopyridine 509 was placed and reacted at 95°C for 8 hours.

Thereafter, treatment was carried out in the same manner as in Example 1 to obtain 2-bromo-6=methylaminopyridine 229.

Next, examples of compounds obtained from the compounds of the present invention and their use as herbicides will be shown.

The compound of the present invention, 2-bromo-6-methylaminopyridine, is converted into 2-methoxy-6 by reaction with sodium methoxide.
-Methylaminopyridine (boiling point 88-92℃ 7 s m
+XI (g) with the same amount of anhydrous potassium carbonate at 20 m
Stir in 1 liter of acetone, 2 dissolved in 20 ml of acetone.
-naphthyl chlorthioforme) 2.239 was added, and 30 minutes later, the reaction mixture was extracted with benzene, washed with water, dried,
Recrystallization gives 0-2-naphthyl N-(6-medoxy2
-pyridyl)-N-methylthiocarbamate 2.759
I got it.

Melting point 95.5-97℃ Elemental analysis value (as C□H, I, N, 'O, S) CHN Analysis value (%) 66.42 4.89 a
81 Theoretical value (%) 66.65 4.97 8
．． 64 diameter? A porcelain bottle) K was filled with paddy soil, water was added, and after puddling, weed seeds were sown on the surface of the soil, and two two-leaf rice seedlings (variety Nipponbare) were planted at a depth of 1 m.

The next day, it was flooded with 2 cm of water and 0-2-naphthyl N-(6-
A wettable powder containing 10% of 7-2-pyridyl)-N-methylthiocarbamate was diluted to 10% water per pot and dropped onto the water surface.

Thereafter, the plants were left in a greenhouse and 3 weeks after the chemical treatment, the herbicidal effect and the effect of tV on paddy rice were investigated.

As a result, the test chemical 1259/j Oa caused no chemical damage to paddy rice seedlings, and 100% controlled wild grass, Japanese cypress, firefly, Japanese cypress, and Japanese grass.

Patent applicant: Toyo Soda Kogyo Co., Ltd.

Claims (1)

[Claims] 1) 2-bromo 6-methylaminopyridine 2) 2.6
- A method for producing 2-bromo-6-methylaminopyridine, which comprises reacting dibromopyridine and methylamine.