JPH0324463B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to 4-(2'-norbornadienecarbonyloxy), which is a type of benzophenone derivative.
This invention relates to benzophenone, its production method, and optical energy storage materials using it.

In recent years, research has been conducted from various fields on how to effectively utilize the solar energy that living things on earth enjoy. One such field is the conversion of light energy into chemical energy, and research is being conducted into using sunlight as light energy and storing this as chemical energy in a conversion agent. Here, the conversion of light energy into chemical energy means, for example, that sunlight is irradiated onto a chemical substance, and the chemical substance (represented by the symbol A, for example) is photoisomerized by the sunlight's light energy, and the chemical bond is A so-called strain compound having a strain of (for example, this strain compound is represented by the symbol B)
means to obtain as. The energy thus converted into chemical bond energy is released as heat when compound B is converted into the original compound A using appropriate means as needed. Therefore, this compound A functions as a light energy storage material.

As research from this point of view, for example, norbornadiene-quadricyclene system (compound A
However, as norbornadiene only absorbs short wavelength ultraviolet rays and hardly absorbs sunlight, norbornadiene must be used in combination with a so-called sensitizer. No.

In addition, as an alternative to sensitizers to make it easier to absorb sunlight, there is also a known method of introducing functional groups such as electron-donating groups and electron-withdrawing groups into norbornadiene. The production of such derivatives requires a long reaction process and cannot be called an industrial method.

On the other hand, phototautomerization between the cis-trans isomer of olefins may cause a dark reaction from the cis-form to the trans-isomer, which wastes energy and is unsuitable for energy storage.

In view of this point, the present inventors have conducted extensive research into optical energy storage materials that can easily absorb sunlight and withstand long-term storage, resulting in the present invention.

That is, the 4-(2'-norbornadienecarbonyloxy)benzophenone (abbreviated as the present compound) of the present invention can easily absorb sunlight and cause a photoisomerization reaction. Furthermore, it was discovered that this compound has an extremely high photoisomerization rate and exhibits unprecedented performance because the part that absorbs sunlight is chemically bonded to the part that generates strain. For example, dissolve this compound in benzene and expose it to sunlight for a short period of time (approximately).
30 minutes), it is converted into 4-(1'-quadricyclenecarbonyloxy)benzophenone (hereinafter abbreviated as Q-isomer) represented by the formula ().

This Q-form does not change even after long-term storage, and can be returned to its original state by contacting it with AgBF ₄ , Rh(CO) ₄ Cl ₂ , metal porphyrins, etc., in a solvent or without dissolving it in a solvent. Upon conversion to this compound, approximately 18 Kcal/mol of heat is generated. Moreover, the reconstituted compound of the present invention can of course be used repeatedly. In this way, this compound can store light energy such as sunlight in the form of chemical energy, and this can be extracted at any time as thermal energy etc., making it a practical light energy storage material. It is something.

Next, the method for producing this compound will be described. This 4
-(2'-Norbornadienecarbonyloxy)benzophenone is a Daleth compound of 4-propioloyloxybenzophenone and cyclopentadiene.
It can be produced by Alder reaction. In addition, 4-propioloyloxybenzophenone used at this time is 4-propioloyloxybenzophenone according to the method described in the specification of Japanese Patent Application No. 129363/1983 (see Japanese Patent Application Laid-open No. 23341/1983) filed by the present applicant. - Can be produced by condensation of hydroxybenzophenone and propylic acid. This Diels-Alder reaction is carried out in the presence of a solvent or in the absence of a solvent at -20°C to 100°C, preferably at 10°C to 30°C. When using solvents, ether-based, halogen-based, ester-based,
Various aromatic solvents can be used.

Moreover, this 4-(2'-norbornadienecarbonyloxy)benzophenone can also be produced by condensation of 4-hydroxybenzophenone and 2-norbornadienecarboxylic acid. i.e. 4
-Hydroxybenzophenone and 2-norbornadienecarboxylic acid are dissolved in an inert solvent such as an ether type, ester type, halogen type, or aromatic type, and N,N'-dicyclohexylcarbodiimide is added thereto as a condensing agent. It can be produced by reacting at a temperature of 80°C to 80°C, preferably 10°C to 40°C. A stoichiometric amount of N,N'-dicyclohexylcarbodiimide is sufficient in this case.

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but these Examples do not limit the present invention in any way.

Raw material production example 4 - Production of propioloyloxybenzophenone 19.8 g of 4-hydroxybenzophenone and 8.0 g of propiolic acid were dissolved in 200 ml of ethyl acetate.
21.0 g of N,N'-dicyclohexylcarbodiimide was added thereto, stirred and reacted at 20°C for 40 hours, the precipitate formed after the reaction was separated, the solvent was distilled off from the liquid under reduced pressure, and the residue was purified by column chromatography. Purification was performed to obtain 19.2 g of white crystals. The physical properties of the product were as follows, and it was confirmed that it was 4-propioloyloxybenzophenone.

Melting point 91.0-91.5℃; Ultraviolet absorption spectrum, λmax (ε) = 255 nm (17100) Acetonitrile; Nuclear magnetic resonance spectrum ( ^1H , _CDCl3 , δ value) 3.10 (S, 1H); 7.20-7.90 (m, 9H) Example 1 4-propioloyloxybenzophenone 5.0
g and 5.0 g of cyclopentadiene were dissolved in 30 ml of dichloromethane, and the mixture was stirred and reacted at room temperature for 20 hours. After the reaction, the reaction solvent was distilled off under reduced pressure, and the resulting oil was purified by silica gel column chromatography to obtain 5.20 g of 4-(2'-norbornadienecarbonyloxy)benzophenone.
was obtained as white crystals. Yield 82.3%. Next, the physical property values are shown.

Melting point 127.0-127.8℃ Nuclear magnetic resonance spectrum ( ¹ CD ₂ Cl ₂ ) δ value 2.10-2.37 (m, 2H); 3.68-3.85 (m, 1H); 3.93-4.07 (m, 1H); 6.68-6.83 (m , 1H); 6.90-7.05 (m, 1H); 7.17-7.96 (m, 9H, 1H) Infrared absorption spectrum (cm ^-1 ) (KBr) 3000, 1720, 1642, 1590, 1445, 1415, 1320,
1280, 1205, 1165, 1145, 1035, 1015 Ultraviolet absorption spectrum (dichloromethane) λmax (ε) = 258 nm (23900) Elemental analysis values, ( ) are calculated values C: 79.75% (79.73%), H: 5.11% ( 5.10%) Example 2 4-propioloyloxybenzophenone 6.5
g and 8.0 g of cyclopentadiene were dissolved in 40 ml of ethyl acetate, and the mixture was stirred and reacted at room temperature for 40 hours. Thereafter, it was treated in the same manner as in Example 1, and 4-(2'-
6.85 g of norbornadienecarbonyloxy)benzophenone was obtained. Yield 83.4%. The physical properties were the same as in Example 1.

Example 3 4-propioloyloxybenzophenone 7.2
Mix and dissolve g and 9.0 g of cyclopentadiene.
The reaction was stirred at 20°C for 45 hours. Thereafter, a small amount of ethyl acetate was added to the reaction solution, and the target product was separated and purified by column chromatography to obtain 8.0 g of white crystals. The physical properties of this substance were the same as in Example 1, and it was identified as 4-(2'-norbornadienecarbonyloxy)benzophenone.

Yield 88.0% Example 4 A solution in which 9.9 g of 4-hydroxybenzophenone and 6.8 g of 2-norbornadienecarboxylic acid were dissolved in 50 ml dichloromethane, and 10.3 g of N,N'-dicyclohexylcarbodiimide was dissolved in 50 ml dichloromethane. was added and stirred at room temperature for 40 hours.

After that, the precipitate that had formed was separated, and the liquid was concentrated under reduced pressure to obtain 19.8 g of oil. This oil was purified by silica gel column chromatography to obtain 14.3 g of white crystals. Yield 90.5%. The melting point and other physical properties are the same as in Example 1.
It was identified as -(2'-norbornadienecarbonyloxy)benzophenone.

Example 5 4-(2'-norbornadienecarbonyloxy)
A solution of benzophenone ( ^5.0 column, hexane/ethyl acetate eluent system), the content of 4-(2'-norbornadienecarbonyloxy)benzophenone was 25%, and the remaining 75% appeared as another single peak. . When this peak was fractionated and analyzed by nuclear magnetic resonance spectroscopy, it was found that 4-
It turned out to be (1'-quadricyclenecarbonyloxy)benzophenone. Nuclear magnetic resonance spectrum results ( ^1H , _CDCl2 , δ value) 1.50-1.89 (m, 2H); 2.03-2.40 (m, 2H,
1H); 2.44-2.78 (m, 2H); 7.10-7.95 (m,
9H) The light-irradiated solution was further analyzed by silica gel normal layer thin layer chromatography, but no decomposition products were observed in only two spots.

Reference Example 6 Cobalt phthalocyanine polymer (Japanese Patent Application No. 58-81285 (Japanese Unexamined Patent Publication No. 58-81285) was added as an isomerization catalyst to 100 ml of the solar irradiated liquid obtained in Example 5.
206052 (see Publication No. 206052)) was added, vigorously shaken for 30 minutes, and analyzed using high performance liquid chromatography as in Example 5. Result 4-
Only the peak of (2'-norbornadienecarbonyloxy)benzophenone is shown. Analysis by thin layer chromatography also showed a single spot.

Claims (1)

[Scope of Claims] 1 4-(2'-norbornadienecarbonyloxy)benzophenone represented by formula (). 2. A method for producing 4-(2'-norbornadienecarbonyloxy)benzophenone, which comprises reacting 4-propioloyloxybenzophenone and cyclopentadiene. 3. A method for producing 4-(2'-norbornadienecarbonyloxy)benzophenone, which comprises condensing 4-hydroxybenzophenone and 2-norbornadienecarboxylic acid. 4. A light energy storage material containing 4-(2'-norbornadienecarbonyloxy)benzophenone represented by formula () as an active ingredient.