JPH01242560A - Production of o-aminophenols - Google Patents

Abstract

PURPOSE:To obtain the subject compound useful as a developing agent for photography, etc., in one step and high yield, without separating intermediate, by subjecting salicylhydroxamic acids to Lossen rearrangement reaction. CONSTITUTION:The o-aminophenols of formula I can be produced from the compounds of formula II (V1-V4 are H, alkyl, halogen, nitro, carboxyl, etc.) by Lossen rearrangement reaction. The reaction is carried out e.g., by using 2-3mol-equivalent of KOH based on the compound of formula II, preparing the compound of formula IV without separating the compound of formula III and reacting the compound of formula IV, without separating from the system, at 50-100 deg.C, preferably 80-100 deg.C to obtain the compound of formula V. Without separating the product, it is made to react with 1-10mol-equivalent of KOH based on the compound of formula II to obtain the objective compound of formula I.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for synthesizing 0-aminophenols, and more specifically to a method for producing 0-aminophenols with good yield. be.

(Prior art) 0-7 minophenols are used themselves as modern chemicals for photography, and are also useful as intermediates and raw materials for the synthesis of functional compounds such as sensitizing dyes, dyes, laser dyes, and couplers for light-sensitive materials. It is.

As a method for synthesizing this more 0-aminone enol,
A synthetic method that makes full use of the Rossen rearrangement reaction is known. For example, there is the method shown below (knee double: x, −
・Scott (A, W, 5cott), J, H, Mo to), Journal・
of the American Chemical Industry (J
, Am, Chem, Soc, ) i4'2 Volume 1.2! μ!
-2j≠Refer to miscellaneous texts such as Risada (1999), the literature describes up to the oxacylone form) Oxacylone form (problem to be solved by the invention) In route (A) above, the oxacylone form is generated during the reaction. Intermediates had to be isolated sequentially to remove by-products and excess reaction reagents. As a result, the target product was reduced, and as a result, the overall yield from salicylhydroxamic acids could not be said to be high. For example, the overall yield of copemino-3-naphthol is 37%, which is not good.

The same is true for coamino-monochlorophenol, and the total yield is λ! I can't say that it's good to be in charge.

Therefore, it is desired to develop a high-yield synthetic method that can be widely applied to o-aminophenols.

Seven methods for increasing isolation yields include using intermediates without purification to avoid purification losses; This often results in giving a reaction mixture, which actually reduces the yield.

(Means for Solving the Problems) The present invention provides intermediates for producing 0-aminophenols represented by the general formula (I) from salicylhydroxamic acids represented by the following general formula (II) using a Rossen rearrangement reaction. o-, which is characterized in that it is synthesized by the -kan method without isolating the o-
This is a method for producing aminophenols.

General formula (I)
child, alkyl group,...rogen atom, carboxy group, hydroxy group, nitro group, alkoxy group, or aryl s
In the t-indication, vl and V2, v2 and v3, and v3 and v4 may form a fused ring. Note that the alkyl group may be further substituted with a substituent. ) General formula (It) (wherein vl, ■2, Va, and v4 have the same meanings as in general formula (I)) Next, V□ in the compound represented by the soft formula (I) and (If) above, v2, v3, and V4 will be explained in more detail.

Vl, V2, Va, V 4,! : L"Q;j, which may be the same or different from each other, each hydrogen atom, unsubstituted alkyl group with carbon number io or less (e.g. methyl group, ethyl group, etc.), carbon number/r or less substituted alkyl group (e.g. benzyl group, α-naphthylmethyl group, λ-phenylethyl group, trifluoromethyl group), halogen atom (e.g. chlorine atom, fluorine atom, bromine atom, iodine atom), carboxyl group, hydroxy group, nitro group, carbon number io The following alkoxy groups (eg, methoxy group, ethoxy group, benzyloxy group, etc.) and aryl groups (eg, phenyl group, tolyl group, etc.) are preferred.

Vl,! :V2. Vz and Va, and Va and V4 may form an M-side mass.

For example, a condensed ring composed only of carbon atoms [for example, an unsubstituted benzene ring, a benzene ring with a substituent (for example, an unsubstituted alkyl group having 10 or less carbon atoms (for example, a methyl group, an ethyl group), Substituted alkyl groups having less than lr carbon atoms (e.g. benzyl group, α-naphthylmethyl group, λ-phenylethyl group, trifluoromethyl group), halokene atoms (e.g. chlorine atom, fluorine atom, bromine atom,
iodine atom), carboxy group, hydroxy group, nitro group, alkoxy group having less than io carbon atoms (e.g. methoxy group,
(ethoxy group, benzyloxy group, etc.), aryl group (eg, phenyl group, tolyl group, etc.) are preferred. ) Cyclopentadiene ring, tropylidene ring, etc.] Or a heteroatom-containing gold ring (for example, a substituted or unsubstituted pyridine ring, furan ring, thiophene ring, pyrrole ring, thiazole ring, oxazole ring, imidazole ring, triazole ring, etc.) etc. are preferable.

Particularly preferred is a substituted or unsubstituted benzene ring.

The reaction method according to the method of the present invention specifically follows the following route, but it is carried out in an integrated manner without isolating intermediates during the process.

(II) (III) (W) (V) (I) (In the formula, v1, ■2, v3, and v4 have the same meanings as above.) Next, the consistency method will be explained in detail.

(1) Synthesis of Compound (III) It is preferable to react the compound represented by the general formula (II) using acetic anhydride in an amount of /~/, j molar equivalents, preferably s'~/, J molar equivalent. is more preferable. If 1 molar equivalent of acetic anhydride is not used, the yield decreases significantly9.
/, if the amount exceeds 1 molar equivalent, the production of by-products will increase.

The reaction temperature is preferably 1O-1000C, more preferably 0C! If the temperature is less than 100C, the reaction progresses slowly and it is difficult to completely eliminate the raw materials. If the amount is exceeded, the yield will be low due to the formation of by-products.

The reaction is preferably carried out under appropriate stirring.

The solvent used for the reaction is water, alcohol (e.g. methanol, ethanol, isopropyl alcohol, etc.)
, acetonitrile, etc., and one or more of them can be used in consideration of reaction conditions, boiling point, solubility, reactivity, odor, price, etc.

(11) Synthesis of compound (R') Next, without isolating the compound represented by general formula (III), 4 to 3 ml of KOH was added to the starting material, the compound represented by general formula (II). It is preferable to carry out the reaction using molar equivalents of λ to co.

It is more preferable to use Hiromolar equivalents. If the amount of KOH is less than 2 molar equivalents, the yield will decrease significantly, and if it exceeds 3 molar equivalents, the production of by-products will increase.

The reaction temperature is preferably 0 to 300C, preferably 10-2!0C; if the temperature is below 0C, the reaction progresses slowly and it is difficult to completely eliminate the raw materials. If it exceeds 300 (:), the yield will be low due to the formation of by-products.

The reaction is preferably carried out under appropriate stirring.

(+i+) Compound (V) is produced by heating the synthetic carbon of compound (V) without isolating compound (M).

Choose the reaction temperature! θ ~ 1000 (: 1000C, more preferably ? The yield is low due to the formation of

The reaction is preferably carried out under appropriate stirring.

(IV) Synthesis of Compound (I) Next, without isolating Compound (V), KOH was added to the starting material of the compound represented by the general formula (II) for 7 to 7 minutes.
It is preferable to carry out the reaction using 10 molar equivalents, and 2
It is more preferable to use ~5 molar equivalents. When KOH is less than 1 molar equivalent, the yield decreases significantly, and when it exceeds 70 molar equivalents, the production of by-products increases.

Preferably the reaction temperature! 0-1000(:), more preferably 10-1000C, and the temperature is joo(:
If it is less than 1,000 (:), the reaction progresses slowly and it is difficult to completely eliminate the raw materials, and if it exceeds 1,000 (:, the yield will be low due to the production of by-products.

When a solvent with a low boiling point is used, it is preferable to perform hydrolysis after distilling off the solvent because the reaction proceeds smoothly.

The reaction is preferably carried out under appropriate stirring.

Next, specific examples of the compound represented by the general formula (I) synthesized by the method of the present invention will be shown. (-For the compound represented by the soft formula (It), the -NH2 group in the following specific example is replaced by -CONH
Examples include those with different OH groups. ) compound/ compound co-compound! Compound 7 Compound! Compound//Compound/Compound/3
Compound/≠Compound/j Compound 16 Compound 17 Compound/Ir compound l
Compound 1O Compound 2/
Compound 22 (Effect of the Invention) According to the method of the present invention, various 0-aminophenols can be obtained in one step and in high yield.

The O-aminophenols obtained according to the present invention can themselves be used as photographic developers.

Furthermore, the usefulness of these 0-aminophenols is that these compounds can be used as intermediates or raw materials for the synthesis of functional compounds such as photosensitive sensitizing dyes, dyes, laser dyes, and couplers.

According to the present invention, o having various tlt substituents is relatively free.
-Since it has become possible to synthesize aminophenols, it has become possible to control the properties of the above-mentioned dyes (for example, photographic sensitivity, storage stability, etc.) over a wide range.

(Example) Next, the present invention will be explained in more detail based on examples.

Examples / <Synthesis of Compound 3> (1) Synthesis of Hiro-chlorosalicylhydroxamic acid H.Penjagen (H, B6shagen), Hemitsz Berichte (Chem, Ber) Htoo volume, p.
,Pj! Dissolve IJium, 2r1 in 1 oz of water and add hydroxylamine hydrochloride λ/1 and 20 ml of water in nitrogen.
In addition to the solution in step 1, an aqueous hydroxylamine solution was prepared. This solution was stirred vigorously and a solution of Hiro-chlorosalicylic acid ethyl ester O2 and 100 sJ of dioxane was slowly added thereto.

After addition, the solution was further stirred at 2t'C/j' for a clear solution. The reaction mixture was concentrated to half volume using a rotary evaporator under reduced pressure and acidified with hydrochloric acid to precipitate white crystals. Remove this with suction filtration and use isopropyl alcohol! After washing with 0#, 4tJ of white crystals of goochlorosalicylhydroxamic acid were obtained. (Yield 7jl
)was gotten.

m, p, were /20~/coloC.

(11) Synthesis of Compound 3 The above 3t2 of Hiro-chlorosalicylhydroxamic acid, 370 ntl of acetonitrile, and J/l of acetic anhydride were mixed and stirred outside @j00c for 7 hours. KOH to reaction mixture
2 to 1 and 00 td of water were added, and the mixture was heated under reflux for 2 hours. Next, acetonitrile is distilled off and KOH≠j? and water 200-
was added and refluxed for μ hours. Cool the reaction mixture on ice.
When neutralized with α, white crystals were precipitated. Take this out with suction filtration, dry it, and it's ready! -299 chlorophenols were obtained. (yield 100%) m, p, are 1
4to~l≠t (Ic.

Example 3 Synthesis of Compound ≠ 3-chlorosalicylhydroxamic acid was synthesized according to the method (1) of Example.

This compound 31? and acetonitrile J70ytl and acetic anhydride co/P were mixed and stirred for 1 hour at an external temperature of 100 (:). KOH coco 2 and water 200 ml were added to the reaction mixture,
The mixture was heated under reflux for 2 hours. Next, ace)nitrile is distilled off, and K
OH≠j? and -200 d of water were added and refluxed for μ hours. Cool the reaction mixture with HCl! Upon neutralization, white crystals were precipitated. This is filtered with suction and dried, resulting in 2-amino-2-chloroa phenol! 2? was gotten.

(Yield 100%) m, p, /311 ~ /j/l
'C.

Example 3 Synthesis of Compound 7〉According to the method of Example 1 (1), 3-hydroxy-2
-Synthesized naphthalene hydroxamic acid.

4 tOf this compound, 370 d of acetonitrile, and 2/2 acetic anhydride were mixed and stirred at an external temperature of zo0c for 1 hour.

KOH2λ2 and 200 td of water were added to the reaction mixture, and the mixture was heated under reflux for 2 hours. Next, acetonitrile was distilled off and KOH
4 Ljf and 200 tnl of water were added and refluxed for a period of time. The reaction mixture was cooled with water and then neutralized with Hα to precipitate white crystals. This is taken out by suction filtration and dried, resulting in 2-
Amino-3-naphthol 3λt was obtained. (yield io
o4) m, p, were l rich 0C.

Patent Applicant: Fuji Photo Film Co., Ltd. Procedural Amendment The month of 1986 ended with Ahi.

Claims (1)

[Claims] O-aminophenols represented by the following general formula (I) are produced from salicylhydroxamic acids represented by the following general formula (II) using a lotusene rearrangement reaction without isolating an intermediate, and by an integrated process. A method for producing o-aminophenols, the method comprising: General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, V_1, V_2, V_3, V_4 are hydrogen atoms,
Indicates an alkyl group, halogen atom, nitro group, carboxyl group, hydroxy group, alkoxy group, or aryl group, V_1 and V_2, V_2 and V_3, V_3 and V_4
may form a condensed ring) General formula (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, V_1, V_2, V_3, V_4 are the general formula (
I ) has the same meaning as )