JPS62226956A - Production of 4-alkoxyaryl thioether compound - Google Patents

Abstract

PURPOSE:To easily produce the titled compound useful as an additive for heat- sensitive recording material at a low cost suppressing the intrusion of isomers, by reacting a 4-alkoxythiophenol with a sulfonic acid ester of an alcohol or an aliphatic halide. CONSTITUTION:4-Alkoxythiophenol produced by the reduction of a 4- alkoxybenzenesulfonyl chloride is extracted in a nonaqueous solvent with an alkaline aqueous solution. The extracted compound is made to react with a disulfonic acid ester of an alkylenediol or a dihaloalkane in a solvent such as ether at 20-150 deg.C, preferably 40-100 deg.C to obtain the objective compound. The reaction is preferably carried out in an inert gas atmosphere to prevent the coloring of the solution and the formation of disulfite of thiophenols.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a process for producing 4-alkoxyarylthioether compounds useful as additives for recording materials, particularly heat-sensitive recording materials.

(Prior Art) Various methods for producing 4-alkoxyarylthioether compounds have been known, but they have drawbacks such as complicated reaction operations and contamination of isomers.

(Object of the Invention) Therefore, an object of the present invention is to provide an inexpensive and simple method for producing a 4-alkoxyarylthioether compound.

(Structure of the Invention) Recording materials, particularly those having a thioether as a heat-sensitive recording material additive, are suitable for increasing sensitivity, and among these, bis-forms are particularly preferred.

The present invention provides a method for producing a 4-alkoxyarylthioether compound, which comprises reacting ≠-alkoxythiophenol with an alcohol sulfonic acid ester or an aliphatic halide. In particular, the method according to the present invention is favorable for producing the bis form of ≠-alkoxyarylthioether. The sulfonic acid ester of alcohol or the aliphatic halide is preferably a disulfonic acid ester of alkylene diol or a dihaloalkane.

It is particularly preferable to synthesize matacou alkoxythiophenol by a reduction reaction from ≠-alkoxybenzenesulfonyl chloride, since there is less contamination with 〇.

A preferred method of the present invention is as follows.

(II XR3X or R25O3R30SO2R21π) (II
I) Here, R1 represents an alkyl group or an aralkyl group, R2 represents an alkyl group or an aryl group, X represents a norogen atom, and R3 represents a covalent group having a carbon atom number of / to /θ.

More specifically, R1 represents an alkyl group or an aralkyl group, which may be either linear or branched.

In particular, a lower alkyl group having a carbon atom number of j or less, a carbon atom number r
The following aralkyl groups are preferred.

Examples include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, a benzyl group, a goomethylbenzyl group, and a phenoxyethyl group.

R2 represents an alkyl group or an aryl group, but a monoyl group is preferred, and phenyl and p-tolyl groups are particularly preferred.

X represents a halogen atom, preferably a bromine atom or a chlorine atom.

R3 is a divalent group having from 1 to 10 carbon atoms, and particularly preferably linear or branched alkylene, oxaalkylene, thiaalkylene or alkenylene. Among them, linear alkylene-oxaalkylene, polyoxaalkylene-thiaalkylene, etc. having a carbon atom number of 1 or less are excellent in terms of ease of synthesis and ease of product purification.

A compound represented by the general formula [ml] can be easily and inexpensively prepared.
In addition, in order to reduce the amount of by-products produced, it is particularly preferable to carry out the reaction without removing the reaction intermediate during production.

For this purpose, it is preferable to extract the gualkoxythiophenol produced by the reduction reaction of ≠-alkoxybenzenesulfonyl chloride with an aqueous alkaline solution in the presence of a water-insoluble solvent, and then react it with a disulfonic acid ester of an alkylene diol or a dihaloalkane.

Examples of reducing reagents for t-alkoxybenzenesulfonyl chloride include metals, metal salts, metal hydrogen complexes, and hydrazine, such as zinc, iron, tin, tin chloride, sodium borohydride, and hydrazine.

These are preferably reacted under acidic conditions.
For example, it is preferable to use it in combination with hydrochloric acid, acetic acid, sulfuric acid, etc.

When the gualkoxythiophenol produced by this reduction reaction is transferred to a water-insoluble solvent, the water-insoluble solvent may be added in advance of cleaning the reduction reaction, or may be added after the reduction reaction is completed.

As the water-insoluble solvent, hydrocarbon solvents are preferable, e.g.
t Habenzene, toluene, xylene, etc. are removed.

Next, when extracting goualkoxythiophenol from this water-insoluble solution of goualkoxythiophenol with an aqueous alkali solution, the alkali is caustic! - Caustic soda and caustic potassium are preferred, and the pT of the aqueous solution (is 7°
-io, o, preferably 7. J--ri, O are good.

Extraction may be performed while heating if necessary.

In the reaction of gualkoxythiophenol and disulfonic acid ester of alkylene diol or dihaloalkane in an alkaline aqueous solution, heating to about 20 to 1JO0C, combined use of solvents such as alcohols, halogenated hydrocarbons, aromatic compounds, polar solvents, etc. It's okay to do that. In this reaction, as the polar solvent added to the alkaline aqueous solution of gualkoxythiophenol, a solvent having a hydrophilic group such as ether, carzenyl, sulfonyl, cyano, amide, or hydroxyl group is particularly preferred.

For example, methyl ethyl ketone, acetonitrile, dimethylacetamide, acrylonitrile, N-methylpyrrolid/hexamethylphosphoramide, sulfolane, cyclohexanone, dimethylformamide, dimethylsulfoxide, acetone, methanol, ethanol and the like are preferred.

J - These solvents are used in an amount of from 0 to t%, preferably from 70 to 10%, based on the alkaline aqueous solution of t-alkoxythiophenol.
It is better to use %.

In addition, it is preferable to carry out the reaction in an inert lithium atmosphere from the viewpoint of preventing coloring of the liquid and preventing disphite formation of thiophenols. Also, it is possible to use a crown ether or a phase transfer catalyst during the reaction. .

The reaction may also be carried out under pressure, which is particularly preferred when acetone is used as the total solvent.

The reaction temperature is 20°C from the viewpoint of reactivity and decomposition of disulfonic acid ester and dihaloalkano of alkylene diol.
It is preferably 0C or more/5o0C or less, and particularly preferably ≠o'C or more and ioo°C or less.

(Embodiments of the Invention) Example/Pour 170% sulfuric acid 2≠09f into crushed ice, and add dropwise to it while cooling to below o'C while stirring well and adding goomethoxybenzenesulfonyl chloride t2ff. Further, 100 tf of zinc powder was added little by little while being careful not to raise the temperature in the reaction system above 300 C, and after the addition, a reduction reaction was carried out while heating as necessary.

After the reaction was completed, the produced t-methoxythiophenol was extracted with 200% of toluene, and from the toluene extract /
Extract with Jiffy sodium hydroxide aqueous solution rtytt. Next, 2!0 ml of methanol was added to this alkaline extract of ≠-methoxythiophenol and stirred thoroughly, followed by 7≠ of 2-dichloroethane.

was added dropwise, taking care not to allow the internal temperature to rise above 1,000°C. Subsequently, stirring was performed at ≠00C for ≠ hours.

After pouring the reaction mixture into ice water and collecting the precipitated crystals ff1F,
The mixture was thoroughly washed with water and methanol and recrystallized with a mixed solvent of methanol/ethyl acetate to obtain 2-bis(Hiro-methoxyphenylthio)ethane (, mp#)lr-100).

Example λ For example 7.2-dichloroethane/, 4t
The reaction was carried out in the same manner as in Example 1 using -Jp-)lyloxybutane to obtain /,guine (l-methoxyphenylthio)butane (mp10J~3°).

Example 3 A reaction was carried out in the same manner as in Example 7 using t-ethoxybenzenesulfonyl chloride instead of t-methoxybenzenesulfonyl chloride in Example 7. 2-His (≠-
Ethoxyphenylthio)ethane fmp 0-10) was obtained.

Example ≠ Example / Nobi 1 Reacted in the same manner as in Example 1 using normal propioxybenzenesulfonyl chloride instead of methoxybenzenesulfonyl chloride, /, Corbis (≠ - normal propioxyphenylthio) ethane (mp/ //-2°) was obtained.

Example! In place of t-methoxybenzenesulfonyl chloride in Example 1, ≠-isopropioxybenzenesulfonyl chloride F%/, instead of 2-dichloroethane, cordibromoethane was used, and the reaction was carried out in the same manner as in Example/.
, Corbis(Guin-terpropioxyphenylthio)ethane Impt/r-J'
I got l.

Example was reacted in the same manner as in Example/, using t-n-n-butoxybenzenesulfonyl chloride in place of methoxybenzenesulfonyl chloride in Example/, and 2-bis(≠-n-n-butoxyphenylthio)ethane (mp
/ 02-3°)'l! Ta.

The following compounds were obtained in the same manner.

/)1. λ-bis(goubenzyloxyphenylthio)
Ethane 21/, 1Lt-bis(coubenzyloxyphenylthio)butane 1. ．． 2-bis(-(gumethylbenzyl)oxyphenylthio)ethane 4!1/, -bis(4t-(+-chlorobenzyl)oxyphenylthio)ethane/, Corbis(4t-(2-7 enoki) ethyl)oxyphenylthio)ethane2) Bis(2-(≠-methoxyphenylthio)ethyl)sulfide7) Bis(,2-(#-benzyloxyphenylthio)
Ethyl) ether? ) /, 7-bis(ll-methoxyphenylthio)-3,! -dioxahebutane

Claims (1)

[Claims] A method for producing a 4-alkoxyarylthioether compound, which comprises reacting 4-alkoxythiophenol with an alcohol sulfonic acid ester or an aliphatic halide.