JPS5925344A - Preparation of 2-chloro-4-fluorophenol - Google Patents

Abstract

PURPOSE:To obtain the titled substance useful as a raw material for a herbicide such as a hydantoin derivative, etc. in high purity in high yield, by chlorinating 4-fluorophenol with sulfuryl chloride in the presence of an N-containing base such as an amine, acid amide, urea, etc. CONSTITUTION:4-Fluorophenol is chlorinated with 1-1.5 equivalent sulfuryl chloride in the presence of an N-containing base, to give the titled substance. A primary amine (e.g., butylamine), secondary amine (e.g., diethylamine), tertiary amine (e.g., triethylamine), acid amide (e.g., formamide), urea, or a mixture of them is preferably used as the N-containing base, the amount of it used is preferably 0.005-2wt% based on the raw material compound. Dichloromethane, chlorobenzene, etc. is used as a reaction solvent, if necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relies on the chlorination of gufluorophenol with sulfuryl monochloride in the presence of nitrogen-containing UK groups! - Chloro-fluorophenol production method.

2-Chloroder fluorophenol obtained by the production method of the present invention is a compound that is an active ingredient of a herbicide, such as Patent V Shoj Otsu-4t7 No. 76, Patent Application Shoj Otsu-9337.
M [i
It is useful as a raw material compound for hydantoin conductors, tetrahydrophthalimide conductors, and urazole derivatives.

For the preparation of 2-chlorofluorophenol by chlorination of seafluorophenol, see N. F., Kolomieta et al., Zh. Obach.

Khinh 37 (//), 2'1gA-7 (/
9 Otsu 7); C, 4 points//ri! θθz (/c
76K), N., BIIzyuk et al., ny
ul, IzobreLi Tovnrnykh, Zn
akovno! 4L (wa) 2θ; C, A, -Ao
, 2g33;c (/26) etc. have the notation ψ. However, all of these production methods have low yields of 2-chloro-gufluorophenol, and produce by-products such as co-6-cyclofluorophenol, which are difficult to separate, or produce 2-chloro-gufluorophenol, which is a raw material that is not chlorinated. Gnoll remains.

As a result of intensive studies on these production methods, the inventors of the present invention discovered that fluorochlorophenol was produced by chlorinating fluorophenol with sulfuryl chloride in the presence of a nitrogen-containing base.

The production method of the present invention makes it possible to produce highly pure 3-chloro-fluorophenol in extremely high yield from readily available raw materials.

Examples of nitrogen-containing bases used in the production method of the present invention include ammonia, -class amines (e.g., butylamine, α-phenethylamine, β-phenethylamine, aniline, ethanolamine, etc.), secondary amines (e.g., diethylamine, dibutylamine, jetanol, etc.). amines), tertiary amines (e.g. triethylamine, tributylamine, triethanolamine, N,N-dimethylaniline,
Broom-containing heterocyclic compounds such as N,N-diethylaniline (e.g., pyridine, piperidine, imidazole, morpholine, quinoline, etc.), acid amides (e.g., formamide, N,N-dimethylformamide, acetamide,
(N,N-dimethylacetamide, etc.), urea, etc., as well as tertiary amines, secondary amines, tertiary amines, acid amides, urea, and mixtures thereof. Further, these element-containing bases may be salts or other derivatives thereof. The amount used is θ in weight ratio to the raw material goo-fluorophenol. 00/% to /θchi, preferably θ, Ij% to 1? It is strong.

The reaction solvent does not necessarily need to be used, but when used, dichloromethane, chloroform, dichloroethane, chlorobenzene, etc., which are commonly used in chlorination reactions, can be used. When used directly, it is usually added gradually to the fluorophenol or its solution.

After the reaction is completed, a conventional chlorination post-treatment such as washing with an aqueous solution of sodium bicarbonate or the like is performed, and the solvent is distilled off to produce high-purity cochlorine-fluorophenol in a high yield. Of course, it can be further purified by distillation, column chromatography, etc., if necessary.

Next, examples and comparative examples will be shown.

Example/After heating and insulating goofluorophenol at 56°C to melt it, triethalamine θ. Moth 2 was added. Then Ji.
I-ized sulfurirta θ3.0? (11.416 mol×
/． j) was added dropwise over a period of 17 hours and 30 minutes, and then aged at the same temperature for 2 hours and 3θ minutes. The reaction mixture was poured into ice water and stirred for several minutes to separate the layers, then SS sodium bicarbonate aqueous solution/l was added and stirred for 76 minutes. After separation, the mixture was distilled under reduced pressure to obtain colorless liquid 3-chlorofluorophenol. K
The ink was 99%, and the yield relative to fluorophenol was the same.

Example ρ q-Fluorophenol //. 2.0 P (7.0
mol) was heated and kept at 50°C to melt it, and then 0.3 gy of triethylamine was added. Then, under stirring, heat
Sulfuryl chloride/'l/. at 0°C. 7! ;? ( /
．． After 0 mol x θj) was added dropwise over a period of 17 hours and 30 minutes, the mixture was aged at the same temperature for 3 hours. After cooling, 3θθm/ml of ether was added to the reaction mixture, poured into ice water, stirred for several minutes to separate the layers, and then 3θθml of j% sodium bicarbonate aqueous solution was added/ml pressed for θ minutes.

After separation, the ether was removed under reduced pressure to obtain pale yellow liquid 11-chlorofluorophenol as a residue. The purity was 97%, and the yield relative to fluorophenol was 2.5%. He's talented. 2.

6-Cyclolog-fluorophenol content o.
g% was 0 Example 3-S q-Fluorophenol//. ．． 25' (0.1 mol)
After heating and keeping at 3θ°C to melt, the following catalyst was heated to θ. θ3
Added 2 pictures. Then, under stirring, sulfuryl X), 2K 9 (θ, 7 mol X /,!; )
was added dropwise over a period of 30 minutes, and samples were immediately sampled to analyze the contents of gou-fluorophenol, λ-chloro-fluorophenol, and 2,6-cyclo-fluorophenol using the gas chromato method. The results are shown in the table below.

(Component A; 2-chlorofluorophenol component B; -2t A-dichloro-fluorophenol component O; q-fluorophenol comparison/Gfluorophenol 100.θg (6059 mol)
After heating and melting at 50℃, sulfuryl chloride/i(0,g9'Ele×/, 2) was heated at 55 to 6θ℃ with stirring.
was added dropwise over a period of about 3 hours and 30 minutes.

Further, the mixture was heated to around 0°C and stirred at the same temperature for about 70 hours. After cooling, ether qθθyd was added to the reaction mixture, and the mixture was poured into ice water and stirred for several minutes. After that, a liquid Lj% aqueous solution of sodium bicarbonate lθθ,/ was added and stirred for 70 minutes. After separation, the ether was removed under reduced pressure, and 3-chloro-gufluorophenol as a pale yellow liquid was recovered by distillation under reduced pressure. The yield of q-fluorophenol was SS%.

Comparative Example 1 5 fluorophenol//, 29<03 mol)
After incubation + yh at 0°C, sulfuryl chloride J, Jy (θ, 7 mol x 8 s) was added dropwise over 3θ minutes while stirring at the same temperature, and immediately sampled and placed on a gas chromatogram in the same manner as in Examples 3 to S. After stirring at 50°C for 5 hours, the mixture was analyzed in the same manner. The results are shown in the table below.] Components ASB and C are as described above.

Comparative Example 3 Gufluorophenol //0.2g (θ, 1 mol) was melted at 50°C, heated to 9°C, and with stirring, sulfuryl chloride, 27.0y (θ, 1 mol x 1) was added. was added dropwise over 3θ minutes. After further stirring at the same temperature for 79 hours, samples were analyzed using the gas chromatography method, and the contents of 2-chloro-gu-fluorophenol, 1,6-cyclo-fluoro-fluorophenol, and go-fluorophenol were j g, 6%, /3. ．． 2%, Katana, Tachi.

Claims (1)

[Claims] (1) Process Q for producing 2-chloro-gufluorophenol, characterized by chlorinating gou-fluorophenol with sulfuryl chloride in the presence of a nitrogen-containing base. The production method according to claim 1, characterized in that the urea is an amine, an acid amide, and a 2% nitrogen-containing base is used at a weight ratio of θ, θθ3 to fluorophenol. The manufacturing method according to claim 1 or 2, characterized in that