JPS601153A - 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride and its preparation - Google Patents

Abstract

NEW MATERIAL:1,2-Bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride of formula I . USE:A raw material of high-rigidity polymer. It has high melting point and flame retardance. It has higher reactivity than the compound having ester group or carboxyl group at the terminal group, and can be polymerized under mild polymerization condition. PREPARATION:The compound of formula I can be prepared by reacting 1,2-bis (phenoxy)ethane-4,4'-dicarboxylic acid chloride of formula II with Cl in the presence of a solvent selected from 1-8C chlorinated hydrocarbons and 1-2C chlorinated carbons. The solvent is e.g. chlorobenzene, cholorotoluene, chloroxylene, etc., and the Cl is usually chlorine gas. The preferable molar ratio of Cl/ starting substance is 2-4, especially 2-3.5. The yield can be improved by adding 0.1-2wt%, based on the starting substance, of a Lewis acid, especially iodine to the reaction system.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel aromatic dicarboxylic acid chloride and a method for producing the same.

1,2-bis (2
-Chlorphenoxy)ethane-4,4'-dicarboxylic acid or its ester is known (Japanese Patent Publication No. 50-118
(No. 99) This compound has a high melting point and is flame retardant.

The present inventor conducted extensive research with the aim of providing other novel compounds that can be used as raw materials for similar polymers.

As a result, the following novel compounds were discovered, and at the same time, an advantageous method for producing them was discovered, leading to the present invention.

That is, the present invention provides 1,2-bis(2-chlorophenoxy)ethaneoxy)ethane-4 represented by the following formula fI)
, 4'-dicarboxylic acid chloride with (a) a hydrocarbon having 1 to 8 carbon atoms and (b
) A method for producing a compound represented by the formula tI), characterized in that the compound is reacted with chlorine in the presence of a solvent selected from the group consisting of chlorinated carbons having 1 to 2 carbon atoms.

First, the method of the present invention will be explained, and then the compound of the present invention will be explained.

As the 1,2-bis(phenoquine)ethane-4,4'-dicarboxylic acid chloride used as a starting material, those produced by various methods can be used. For example 1, 2
It can be produced by a method in which -bis(phenoxy)ethane-4,4'-dicarboxylic acid is reacted with thionyl chloride, phosphorus pentoxide, phosphorus oxychloride, or the like.

Examples of the chlorinated hydrocarbon having 1 to 8 carbon atoms and the chlorinated carbon having 1 to 2 carbon atoms used as a solvent include chlorobenzene, chlorotoluene, chloroxylene, dichlorobenzene, dichlorotoluene, trichlorobenzene, and trichloro. Toluene, carbon tetrachloride, hexachloroethane,
Examples include chloroform, dichloroethane, trichloroethane, and tetrachloroethane, and two or more of these can be used in combination, but chlorobenzene, dichlorobenzene, and tetrachloroethane are preferred, and chlorobenzene, 1,1, and 2.2 are particularly preferred. -Tetrachloroethane is most preferably used.

As the chlorine reactant, silicon gas is usually used. Although it is desirable that the chlorine gas be of high purity, it may contain a small amount of components that do not inhibit the reaction or cause side reactions.

The amount of chlorine used is such that the molar ratio of chlorine/starting material is between 2 and
It is preferably 4, particularly preferably 2 to 3.5.

The amount of solvent used must be enough to dissolve the starting material,
For example, when using chlorobenzene as a solvent, 2
It is preferable to use up to 20 times the amount.

As a catalyst in the above reaction, 0.1
~2% by weight of Lewis acids, especially iodine, boron trifluoride,
By the presence of sulfuric acid, most preferably iodine,
Yield is further improved.

Although the reaction can be carried out under normal pressure, increased pressure, or reduced pressure, normal pressure or slightly increased pressure is preferred industrially.

Further, the reaction can be carried out in any manner such as batchwise, continuous or semi-continuous.

After the reaction with chlorine is completed, the product is cooled and the precipitate is passed through the mouth, washed and dried to obtain the desired 1,2-bis(2-chlorophenoxy)ethane-4,
4'': Carboxylic acid chloride is obtained in high yield.

This crude product can also be purified by recrystallization with chlorobenzene, dichlorobenzene, or the like.

The thus obtained dicarboxylic acid chloride of the present invention has a high melting point of 180 to 182°C and is flame retardant.

Therefore, the compound of the present invention has a high melting point and is flame retardant, and can be used as a raw material for highly rigid polymers.

For example, the compound of the present invention is mixed with 1,2-bis(phenoxy)ethane-4,4', which is a known compound and a starting material.
-Compared to dicarboxylic acid chloride, the melting point of proton is 1
It has a temperature of 80-182°C and is extremely insoluble in solvents such as benzene and carbon tetrachloride, but the latter has a melting point of 117-122°C.
It is easily soluble in these solvents.

This is considered to be because, in the compound of the present invention, molecular mobility is reduced due to chlorine substitution in the aromatic ring.

Furthermore, since the compound of the present invention has an acid chloride group at the end, it has higher reactivity than a compound having an ester group or a carboxyl group at the end, and the polymerization reaction can be carried out under typical polymerization conditions.

When the compound of the present invention is reacted with, for example, methyl alcohol, ethyl alcohol or phenol, esters, esters (dimethyl ester, diethyl ester,
diphenyl ester) can be produced. It is also possible to convert dicarboxylic acid dichloride into dicarboxylic acid using an alkali.

EXAMPLES The present invention will be explained in further detail by giving examples below.

Example 1 84.8 y (0.25 mol) of 1.2-bis(phenoxy)ethane-4,4'-6 dicarboxylic acid chloride, 1000 y of monochlorobenzene, and 0.4 F of iodine were placed in a reactor equipped with a reflux device. and heated to 120° C. with stirring. Then chlorine gas 39 F (0,455 mol)
was blown into the solution for 4 hours to react.

The reaction product was cooled to room temperature, and the white precipitate produced was dried daily to obtain white crystals of 89F (yield: 87%). The melting point of this white crystal is 180 to 183°C, and the elemental analysis values shown in the first element confirm that it is 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride. Ta. In addition, the infrared absorption spectrum shows that the starting material 1,2-bis(phenoxy)ethane-4,4'
-The absorption peak of dicarboxylic acid chloride at 1780 cm' disappeared, and the peak of 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride at 1780 cm' disappeared.
It was found that it appeared at 60 cM'.

Table 1 This 1,2-bis(2-chlorophenoxy)ethane-4
,4'-dicarboxylic acid chloride is less soluble in various tm solvents than 1,2-bis(phenoxy)ethane-4,4'-dicarboxylic acid chloride (for example, chloroporm, carbon tetrachloride, methylene chloride)1. In chlorobenzene, orthodichlorobenzene, and nitrobenzene, it dissolves at 5-10% near the boiling point, and in N-methylpyrrolidone, it dissolves at 80%.
It was found that the as is about 30% at ℃.

Example 2 84.8 y (0.25 mol) of 1.2-bis(phenoxy)ethane-4,4'-dicarboxylic acid chloride, 1000 p of dichlorobenzene, and 0.41 y of hyodine were reacted with a reflux device. The mixture was placed in a vessel and heated to 120°C while stirring.

Thereafter, chlorine gas 39 F (0.55 mol) was blown into the solution for 4 hours to cause a reaction.

The reaction product was cooled to room temperature, and the white precipitate produced was separated, washed with benzene, and dried to obtain white crystals of 92F (yield: 90%). The melting point of this white crystal is 18
1 to 183°C, and from the elemental analysis values and infrared absorption spectrum shown in Table 2, it was confirmed that it was the desired 1,2-bis(2-chlorolephenokidineethane-4,4'-dicarboxylic acid chloride). It could be confirmed.

Table 2 Comparative Example 1 3-Chlor-4 according to Japanese Patent Publication No. 50-11899
-1,2-bis(2-chlorophenoxy)ethane-4, synthesized from oxybenzoic acid and ethylene dibromide
315 f (0.85 mol) of 4'-dicarboxylic acid and 5 ml of pyridine were charged into a four-eye flask 51 equipped with a dropping funnel and a reflux device, and 500 liters (6.95 mol) of thionyl chloride was added under stirring. It was dripped from dropping row 1- in 30 minutes. Thereafter, the temperature was raised to 79°C over 1 hour, and the reaction was carried out under reflux for 2 hours. Note that acidic gas (hydrogen chloride gas, etc.) generated from the upper part of the reflux vessel could be neutralized with an aqueous solution of caustic soda. After that, the reflux vessel was removed, a rectification column, a Liebig condenser tube and a fractionation adapter were installed, and excess thionyl chloride, by-product sulfur diacid, hydrogen chloride, etc. were removed under normal pressure and reduced pressure for 1 hour and 30 minutes. Removed.

Thereafter, a reflux vessel was installed again, and 51 ml of ortho-dichlorobenzene was added to dissolve the product at 180°C for 1 hour. After cooling to room temperature, the precipitated crystals were passed through the mouth, thoroughly washed with benzene, and dried to obtain pale yellow crystals 270f (yield 66 g6).

The melting point of the product of I was able to confirm that it was Lido.

Table 3 However, compared to the 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride of Example 1.2, the yield was poor and the color was slightly pale yellow. It can be seen that the purity as seen from the elemental analysis value is also somewhat poor.

Claims (2)

[Claims] (1) 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride represented by the following formula (I). (2) 1,2-bis(phenoxy) 4.4' dicarboxylic acid chloride represented by the following formula +II) as (a)
(b) a chlorinated hydrocarbon having 1 to 8 carbon atoms; and (b) a chlorinated carbon having 1 to 2 carbon atoms;
A method for producing 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid chloride represented by l.