JPH0952889A - Production of polylactones - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently obtain the subject compound useful as a crosslinking agent for a polymer and an organic synthesis intermediate, etc., in one step by reacting a polyol with a (meth)acrylic acid (ester) in the presence of a radical initiator. SOLUTION: The objective polylactones expressed by the formula [A is a residue obtained by removing n-groups of the formula: CR'HOH(R' is H, a 1-10C alkyl or a hydroxyalkyl) from a polyol; R is H or methyl; (n) is an integer of 2-10] are obtained by charging a polyol (e.g.; 1,6-hexanediol) in a reactor, attaching a Dean-Stark trap, heating to 170 deg.C while stirring in a nitrogen atmosphere, dropping a solution obtained by mixing a radical initiator (e.g.; di-tert-butyl ether peroxide) with acrylic acid, methacrylic acid or their esters (e.g.; ethyl acrylate) for 10hrs using a dropping funnel and reacting while continuing further the stirring for 4hrs.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing polylactones, and more particularly to a simple method for producing polylactones useful as a crosslinking agent for polymers and an organic synthetic intermediate.

[0002]

2. Description of the Related Art As a method for synthesizing polylactones, for example, J. Org. Chem.,
42 , 1703 (1977) is known, but this method requires a multi-step synthetic route, which makes industrial synthesis difficult. Therefore, an object of the present invention is to provide a method for efficiently producing polylactones in one step.

[0003]

Means for Solving the Problems The present inventors have completed the present invention as a result of extensive studies on a simple method for synthesizing polylactones. That is, the present invention provides a method for producing a polylactone represented by the general formula (I), which comprises reacting a polyol with acrylic acid, methacrylic acid or an ester thereof in the presence of a radical initiator. To do.

[0004]

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(In the formula, A is n-CR'H from the polyol.
Represents a residue excluding OH group, R represents a hydrogen atom or a methyl group, R'represents a hydrogen atom, or an alkyl group or a hydroxyalkyl group having 1 to 10 carbon atoms, n R'may be the same It may be different. n shows the number of 2-10. )

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. In the present invention, the polylactones represented by the above general formula (I) can be conveniently produced in one step. In the present invention, the particularly preferred polylactones obtained are those represented by the general formula (II). It is the dilactone represented.

[0007]

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(In the formula, B represents a linear or branched alkylene group having a total of 1 to 20 carbon atoms, which may be substituted with a hydroxyl group, and R and R ′ represent the above-mentioned meanings, and R'may be the same or different.) The polyol used in the method of the present invention has a general formula (III) A- (CR'HOH) _n (III) (wherein A, R'and n are as described above). Any polyol can be used as long as it is a polyol represented by
-Propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10- Α, ω of decanediol, 1,12-dodecanediol, 2-methyl-1,8-octanediol, etc.
-Diol, trimethylolethane, trimethylolpropane, pentaerythritol, 1,3-butanediol, glycerin and the like. Α, ω-diols are preferable, and linear α, ω-diols having a total carbon number of 4 to 12 are particularly preferable.

Acrylic acid, methacrylic acid or their esters used in the present invention include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate,
Examples thereof include lower alkyl (alkyl group having 1 to 3 carbon atoms) esters of acrylic acid or methacrylic acid such as methyl methacrylate and ethyl methacrylate, with acrylic acid, methyl acrylate and ethyl acrylate being preferred. The amount of acrylic acid, methacrylic acid or their esters used in the present invention varies depending on how many moles of lactone are attached to the polyol, but for example, all the hydroxyl groups are reacted. In this case, it is preferably 0.2 to 2.0 mol times with respect to 1 mol of the hydroxyl group of the polyol, and 0.5 to
1.5 mol times is more preferable.

Examples of the radical initiator used in the present invention include dialkyl ether peroxide radical initiators such as ditert-butyl ether peroxide, diacyl peroxide radical initiators such as benzoyl peroxide, and azobisisobutyronitrile. Examples thereof include azo radical initiators, etc., but ditert-butyl ether peroxide is preferable from the viewpoint of safety and the like. The amount of the radical initiator used is preferably 0.1 to 50% by weight, more preferably 10 to 20% by weight, based on acrylic acid, methacrylic acid or their esters.

In the method of the present invention, the reaction temperature of the addition reaction between the polyol and acrylic acid, methacrylic acid or their esters may be selected in consideration of the half-life and production scale of the radical initiator used. Usually 0-230
C., for example, when ditert-butyl ether peroxide is used as a radical initiator, it is preferably carried out at 160 to 175.degree. The reaction time is preferably 1 to 24 hours, more preferably 5 to 15 hours. This addition reaction is carried out by dropping acrylic acid, methacrylic acid or an ester thereof with a radical initiator to a polyol, or by adding a polyol, acrylic acid, methacrylic acid or an ester thereof and a radical initiator. There is a method of charging and reacting all at once, but in the latter case, the former method is more preferable because the polymerization reaction easily occurs.

Preferred specific examples of this reaction include the reactions represented by the following reaction formulas (1) to (6). After the reaction, water is added to the reaction solution, and in some cases, an appropriate organic solvent such as chloroform, hexane, xylene, or toluene is added for the purpose of further assisting the layer separation, followed by washing with water,
The desired polylactone can be obtained by purification by vacuum distillation, silica gel column chromatography or the like.

[0013]

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[0014]

[Chemical 6]

[0015]

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

Example 1 250 g (2.12 mol) of 1,6-hexanediol was placed in a 2-liter four-necked flask, equipped with a Dean Stark trap, and heated to 170 ° C. with stirring under a nitrogen atmosphere. Continue stirring vigorously as it is, 400 g of ethyl acrylate containing 60 g (0.41 mol) of ditert-butyl ether peroxide (4.
The (00 mol) solution was added dropwise using a dropping funnel over 10 hours. The mixture was stirred for 4 hours as it was, and then cooled to room temperature. Chloroform was added, washed with water, and the solvent was distilled off to obtain an oil, which was then purified by silica gel column chromatography (developing with chloroform / methanol) and represented by the following formula (IV): 5,5 '-( 1,4-butanediyl) bis [dihydro-2 (3H) -furanone] was obtained as 270 g of white crystals in a yield of 56% (purity 98%).

[0017]

[Chemical 7]

¹ H-NMR of the obtained compound (in CDCl ₃ , TMS
The spectrum is shown in Fig. 1, the ¹³ C-NMR spectrum is shown in Fig. 2, and the IR spectrum (measured by the KBr method) is shown in Fig. 3. The ¹ H-NMR spectrum of FIG. 1 shows δ = 1.35 to 2.10
(Methylene), δ = 2.50 to 2.60 (α-methylene), δ =
The respective signals of 2.35 (β-methylene) and δ = 4.50 (methine) are shown.

Example 2 250 g (2.12 mol) of 1,6-hexanediol was placed in a 2-liter four-necked flask, equipped with a Dean Stark trap, and heated to 170 ° C. under a nitrogen atmosphere while stirring. Continue stirring vigorously as it is, and dicarboxylic acid tert-butyl ether 60 g (0.41 mol) acrylic acid 290 g (4.03 mol)
After the solution was dropped using a dropping funnel over 10 hours,
Cooled to room temperature. Chloroform was added, and after washing with water, the solvent was distilled off and the resulting oil was purified by silica gel column chromatography (developing with chloroform / methanol) to give 5,5 ′-(represented by the above formula (IV). 1,4-butanediyl) bis [dihydro-2 (3H) -furanone] was obtained as 240 g of white crystals with a yield of 50% (purity 98%).

Example 3 320 g (2.00 mol) of 1,9-nonanediol was placed in a 3-liter four-necked flask, a Dean Stark trap was attached, and the temperature was raised to 170 ° C. with stirring under a nitrogen atmosphere. Continue stirring vigorously as it is, 400 g of ethyl acrylate containing 60 g (0.41 mol) of ditert-butyl ether peroxide (4.
The solution (00 mol) was added dropwise using a dropping funnel over 10 hours, and the mixture was further stirred for 5 hours and then cooled to room temperature. Hexane was added, the insoluble portion was removed by filtration, the solvent was evaporated, and then chloroform was added. After washing with water, the solvent was distilled off, and the resulting oil was purified by silica gel column chromatography (developing with chloroform / methanol) and represented by the following formula (V): 5,5 '-(1,7- Heptane diyl)
Bis [dihydro-2 (3H) -furanone] was obtained as 270 g of white crystals in a yield of 50% (purity 99%).

[0021]

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[Brief description of drawings]

FIG. 1 ¹ H-NMR (CDCl _{3 of} the compound obtained in Example 1.
Medium, TMS standard, 200MHz) spectrum.

2 is a ¹³ C-NMR spectrum of the compound obtained in Example 1. FIG.

FIG. 3 is an IR spectrum of the compound obtained in Example 1.

Claims (3)

[Claims] 1. A method for producing a polylactone represented by the general formula (I), which comprises reacting a polyol with acrylic acid, methacrylic acid or an ester thereof in the presence of a radical initiator. Embedded image (In the formula, A represents a residue obtained by removing n -CR'HOH groups from a polyol, R represents a hydrogen atom or a methyl group, R'is a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms, or It represents a hydroxyalkyl group, and n R's may be the same or different, and n represents a number of 2 to 10.) 2. The method for producing a polylactone according to claim 1, wherein the polylactone is a dilactone represented by the general formula (II). Embedded image (In the formula, B represents a linear or branched alkylene group having a total carbon number of 1 to 20, which may be substituted with a hydroxyl group, R and R ′ have the above meanings, and two R ′ are It may be the same or different.) 3. The polyol is an α, ω-diol.
The method for producing the polylactone according to claim 2.