JPS63163826A - Organic nonlinear optical materials - Google Patents

Abstract

PURPOSE:To obtain the titled material which has the large secondary and tertiary nonlinearity, and does not suffer thermal and optical damages caused by a laser ray, and is applicable in a broad wavelength range from a visible ray to an infra-red ray by incorporating a compound contg. a combination of a specific electron donative group and a specific electron attractive group to the titled material. CONSTITUTION:The titled material is composed of an pi electron conjugated compd. shown by the formula D(CH=CH)nA where D is the electron donative group. A is the electron attractive group, (n) is 0 or 1. The electron donative group is exemplified by N,N-dimethylamino phenyl group, and the electron attractive group is exemplified by the group shown by formula I or II. In formula I, R<1> is 1-3 C alkyl or halogenated alkyl group, 1-4 C hydroxy alkyl group, 3-8 C dihydroxy alkyl group or H2C=CR<2>-COO(CH2)p-group [where R<2> is hydrogen atom or methyl group, (p) is an integer of 1-4]. Thus, the titled material does not occur any absorption at a visible range, and has the large secondary and tertiary nonlinearity, and has relatively high melting point and less tendency for suffering the damage caused by the laser ray.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to an organic nonlinear optical material. More specifically, the present invention has large second- and third-order nonlinearities, which are useful in fields such as optical information processing, optical communications, and optoelectronics, and is free from thermal and optical damage caused by laser light. Moreover, it is related to a geometrically nonlinear optical material that has excellent characteristics such as being able to be used in a wide range of applications from visible light to infrared light.

[Prior art 1] A nonlinear optical material is a material that exhibits a second-order or higher nonlinear response under the strong electric field of laser light, and its phenomena include frequency conversion,
In recent years, it has attracted attention as a material for optoelectronics and pure optical computers, as it produces magical effects such as oscillation and switching.

These nonlinear optical materials are broadly classified into Kuroiso materials and hu-1 materials. Conventionally, Kuroiso nonlinear materials include, for example;
A ferroelectric material such as II 2 P O, or 1Nb03 is used. However, these inorganic nonlinear optical materials do not have sufficient optical nonlinearity, and in order to be used industrially, it is necessary to make extremely large single crystals, and strong laser light is required. It has the following disadvantages.

On the other hand, as organic nonlinear optical materials, for example, m-nitroaniline and 2-methyl-tonitroaniline are known. These are used to convert semiconductor laser light into visible wavelengths, but they do not have sufficient optical nonlinearity, are deliquescent, are damaged by laser light, and have an absorption band in the visible range, making it possible to It has drawbacks such as not being able to use optical wavelengths.

[Problems to be Solved by the Invention] The purpose of the present invention is to improve the drawbacks of such conventional nonlinear optical materials, to have large second-order and third-order nonlinearity, and to be resistant to heat generated by laser light. In addition to having no physical or optical damage,
The object of the present invention is to provide a nonlinear optical material that has excellent characteristics such as being usable in a wide range from visible light to infrared light.

[Means for Solving the Problems 1] The present inventors focused on π-electron conjugated compounds having an electron-donating group and an electron-withdrawing group as organic compounds with large nonlinear optical constants. We discovered that the nonlinear optical constant of the combination of and electron-withdrawing group was large.
The present invention has been accomplished.

That is, the present invention provides the following formula: [Itl is O or the number 1 of 1, and alkyl group,
Dihydroxyalkyl group having 3 to 8 carbon atoms or 11□C=CR2-COO(Cll2)p-unit(R
' is a hydrogen atom or a methyl group, p is an integer from 1 to 4)
1 or formula (R3, R', R5 and R6 are hydrogen atoms or have 1 to 1 carbon atoms)
This is an organic nonlinear optical material made of an N,N-dimethylaniline derivative, which is an alkyl group of 3).

The present invention provides an organic nonlinear optical system comprising a π-electron conjugated compound represented by the general formula % (in which D is an electron-donating group, A is an electron-withdrawing group, and 1 is 0 or 1). material, with N,N-trimethylamine/ as the electron donating group.
It is an organic nonlinear optical material that has a phenyl group and a group of formula (1) or (2) as an electron-withdrawing group.

There are various synthesis methods for producing the organic nonlinear optical material of the present invention having an electron-withdrawing group of the formula (III) type, but it is preferable to use a dehydration reaction between an aldehyde and an anoacetic acid ester according to the chemical equation below. Can be synthesized.

NCOOR' At this time, a dehydration reaction was carried out at room temperature for 1 to 5 hours using oxane as a solvent and a basic catalyst such as piperinone.
The organic nonlinear optical material of the present invention can be obtained as a solid product by washing the reactant with a solvent such as alcohol.

As the sia7acetate used here, for example, +1. c-COOCII, 112cmC
00C, II.

112cmC00C21iq t12c
C00CII. 01111, c-C00(C)12)
20+1 H2C-C00(CH2)4011
H2CC00(CH2) Jr H2CC00(CH
2) 2CIIF2CH, OH and the like.

In producing the organic nonlinear optical material of the present invention having the electron-withdrawing group (2), for example, 4-(N,N dimethyl7-7)cinnamaldehyde and cyclopentadiene are mixed in a solvent such as dioxane. It can be synthesized by reaction at room temperature in the presence of caustic potash. In this case, cyclopentadiene having up to four furkyl groups having 1 to 3 carbon atoms as substituents can also be used as a raw material.

[Effect of the invention 1] The compound according to the present invention does not cause absorption in the visible region, has large second-order and third-order nonlinearity, and has a relatively high melting point compared to conventional organic nonlinear optical materials. In addition, it has excellent practicality such as not being easily damaged by laser light,
For example, it is useful for laser detectors, laser light sources, etc., or as devices such as optical arithmetic elements, optical bistable elements, optical waveguide circuits, etc., in optical communication, optical information processing, signal processing, etc.

〔Example〕

The present invention will be explained in more detail with reference to Examples.

The second-order nonlinear optical constant d and the third-order nonlinear optical constant χ(
f) was determined by the following method.

(1) Method for measuring third-order nonlinear optical constant χ(3) Third-order nonlinear optical constant χ(3)I, "Laser spectroscopy" (edited by Hikaru Ota, Gakkai Publishing Center) 230-233 Two-photon described by Beno Measured by excited fluorescence method.

As shown in the schematic diagram of the figure, the sample was crushed and
When a powder sample 2 having a particle size distribution on the order of μm is prepared and the sample 2 is irradiated with a laser beam of wavelength ^ from the laser generator 1, two-photon excited fluorescence is emitted in a wide region on the shorter wavelength side than λ. After separating this light with a filter 3 and condensing it with a lens 4, it passes through a spectroscope 5 and extracts light with a certain wavelength λ'.The intensity of the light is measured by a detector 6, an integrator 7, and a recorder 8. The value of χψ was determined.

(2) Method for measuring second-order nonlinear optical constant d The second-order nonlinear optical constant d was measured by the method described in [Fundamentals of Optoelectronics] (Yari 7, published by Maruzen), pp. 198-199 H-1. The measuring device is shown in the figure.

The obtained crystals were crushed to prepare Sample 2 having a particle size distribution of approximately 5 to 40 μm. Wavelength λ from laser generator 2
When the sample 2 is irradiated with a laser beam of , a second harmonic of half the wavelength is generated. This light was separated by a filter 3 and focused by a lens 4, and then passed through a spectrometer 5 to extract only the second harmonic. The intensity was measured by a detector 6, an integrator 7, and a recorder 8, and the intensity ratio with the incident light was measured to determine the value of d.

Example 1 Cyanoacetic acid methyl ester 2,5y (25+omol
), 3.7 g (25 mol) of 4-(N,N-trimethylamino)benzaldehyde and 0.51 ρ of piperidine were dissolved in 20 ml of dioxane and stirred at room temperature for 1 hour.

The resulting solid was filtered off and washed with a small amount of methanol to obtain 3.9 g (yield: 68%) of a yellow solid. It has a melting point of 141°C and the ultraviolet absorption or vector is λwax (in dioxane): 410 nm, ε=9.2XIO'M'-1
cz-' and 'H-NMR (60 Ml (Z: TMS
/'CDCI 3 ) Spectral measurements confirmed that it had the following structure.

Uf (ppm) Division Attribution Rokubon Ratio Burial Exposure 3.1 6.5
64・Ob 3,0 3 6・6 2.0
2 The third-order nonlinear optical constant of this compound was determined by the method described above and was 3130×10-'2esu.

Example 2 Ethylene glycol monocyanoacetic acid ester 5g (39
5.8 g (39+++IIIo I) of 4-(N,N-dimethylamino/)benzaldehyde and 0.5z& of piperidine were dissolved in Dioxa 220 and stirred at room temperature for 2 hours.

The resulting solid was filtered and washed with methanol to give 5g of yellow solid.
(yield 49%). It has a melting point of 225°C, and its ultraviolet absorption spectrum is λIIIax (dioxane):
410nm, ε=3,8X10'M-'ca+-', 'II-NMR (60M41z: TMS/CDC
l 3) As a result of spectral measurement, it was confirmed that it had the following structure.

3.0s a
6.1 63.8
b 2.0 24.3
2.1 26.6
d d 2,0
2 This compound exhibited third-order nonlinear optical constants with a value of 280×10−” esu.

Example 3 Cyanoacetic acid-3-bromopropyl ester 5 g (24
3.6 g (24 mmol) of 4-(N,N-dimethylamino)benzaldehyde and 0.5*1 piperidone were dissolved in dioxane 2011 and stirred at room temperature for 10 minutes. The resulting solid was separated by filtration and washed with methanol to obtain 5.8 g (yield: 72%) of a yellow solid. This has a melting point of 14
2°C, and the ultraviolet absorption spectrum is λwax (dioxane): 415 nm, ε=4.4X 10'M-'
cm-', IH-NMR (60M1lz:TMS
/CDCIz) As a result of spectrum measurement, it was confirmed that it had the following structure.

2.3 t 2,0 23
．． 1 s b 6.0 63
．． 7 t 2,0 24.
4 t d 2,0 26.
9 d e l, 9 2 The third-order nonlinear optical constant of this compound is 1950X10-':
It was esu.

Example 4 Shea/acetic acid-2,2-dimethylolbutyl ester 21
1 (10 mol), 4-(N,N-trimethylamino)benzaldehyde t' 1.5 g (10III mol) and piperinone 0.5 d were dissolved in dioxane 2011 and stirred overnight at room temperature. The resulting solid was filtered and washed with methanol to obtain 0.7 g of a yellow solid (yield 21%). It has a melting point of 130°C, and its ultraviolet absorption spectrum is λma
x (dioxane): 415 nm, ε=4.6X 10
'H-'cm-' and 'It-NMR(60M)I
As a result of measuring the z:IIMDS/d'-DMSO) spectrum, it was confirmed that it had the following structure.

δ value (ppm) Splitting Attribution Integral ratio Buried bJ
J-0,93,03 1,3b 1.9 2 3.1s・6.16 6.7 d f 1.9 2
The cubic nonlinear optical trajectory of this compound is 450X 10-'
“It was esu.

Example 5 Cyanoacetic acid ester having the structure of formula % formula % 5 g (25 ma + ol)
, 4-(N,N-dimethylamino)benzaldehyde 3
．． 9
Then, the solvent was distilled off and the mixture was left in a refrigerator overnight to crystallize. This was filtered and recrystallized from toluene to form a yellow solid.3.
0 g (yield 37%) was obtained. It has a melting point of 103° C. and an ultraviolet absorption spectrum of IIIax (dioxane): 440r+n+.

ε: 5.3X 10'H-'cm-','
H-NMR (GOMl(z: TMS/CDCI 3)
As a result of spectrum measurement, it was confirmed that it had the following structure.

1.9 s 3.3 33
．． 1 b 6.9 64.
5 s 4.3 45.6
s d 1.0 16.
1 s 1. ．． 0 16
．． 6 dr 2.0 2 The third-order nonlinear optical constant of this compound was 360X 10-'''esu.

Example 6 3.3 g (17 m
mol), 4-(N,N-dimethylamino)cinnamaldehyde 3 g (17 mmol), piperidine 0.5zN
was dissolved in 2 oz. of dioxane and stirred at room temperature for 4 hours.

Then, the solvent was distilled off and the mixture was left in a refrigerator overnight to crystallize.

This was filtered and recrystallized from toluene to obtain 2.2 g (yield 36%) of red solid 1. This has a melting point of 120°C
As a result of spectrum measurement (MHz: TMS/CDCl), it was confirmed that it had the following structure.

δ value (ppm) Split Attribution Integral 1 rule 2.0
3.3 33, Ob
6.5 6 4.4 s 4.1 45
．． 5 d 1.0 16.
1 1,0 16.6
d f 2.2 27, Os
g 1.9 27.3 d
h 2.2 27.8 ad
i O,91 The third-order nonlinear optical constant of this compound was 87XIO-12esu.

Example 7 4-(N,N-dimethyl 7-)benzaldehyde2.
2 g (15 mmol), cyclopentanoene 1 g (1
Dissolve 5 mmol) in 20 mN methanol and add KO
A methanol solution of J+ (0,S)y/10z1) was added and stirred at room temperature for 1 hour. The resulting solid was filtered and washed with methanol to obtain 2.4 g of vermillion baragou (yield 81%).
) was obtained. This compound has a melting point of 103°C, and the ultraviolet absorption spectrum is λmax (DMSO): 420 nm.
, t = 4.9X10'H-'cz-', and 'H
As a result of -NMR (608 Hz: TMS/CDCl*) spectrum measurement, it was confirmed that it had the following structure.

3.1 6.0 66.
6-7.5 b 5.6 5
6.6 d 1.9 2
7.9 d cl 1.8
2 The second-order nonlinear optical constant of this compound is 52X 10-
It was 'esu.

Example 8 p-(N+N-trimethyl7/)cinnamaldehyde 2.0
g (llmmol), cyclopentadiene 0.8g (1
1 mmol) was dissolved in 40 mixed solvents of methanol/nidioxane = 1:1, and KOH m/-ol solvent (0
, 6g/10x1) and stirred at room temperature for 2 hours. The formed crystals are filtered and washed with methanol, reddish-purple powder 1
．． 5 g (yield 59%) was obtained. It exhibits a melting point of +50'c and an ultraviolet absorption spectrum of λI11ax (DMS
O): 450nm, ε=6,3X10'H-'cm-
'H-NMR (60MHz: TMS/CDC
I3) As a result of spectrum measurement, it was confirmed that it had the following structure.

3.1 s 6,0 6
8, Odd 2,2 2 The second-order nonlinear optical constant of this compound was 750X 1O-9esu.

[Brief explanation of the drawing]

The figure shows the constituent countries for explaining the measurement method of second-order nonlinear optical constants and third-order nonlinear optical constants, and shows the number 1 in the figure.
is a laser generator, 2 is a sample, 3 is a filter, 4 is a lens, 5 is a spectrometer, 6 is a detector, 7 is an integrator, and 8 is a recorder.

Claims (1)

[Claims] 1 Formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [m is the number of 0 or 1] In, X is the formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [R^1 has 1 carbon ~3 alkyl group or halogenated alkyl group, hydroxyalkyl group having 1 to 4 carbon atoms,
Dihydroxyalkyl group having 3 to 8 carbon atoms or H_2C=
CR^2-COO(CH_2) p- group (R^2 is a hydrogen atom or methyl group, p is an integer from 1 to 4)] Or formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (R^ 3. R^4, R^5 and R^6 are hydrogen atoms or alkyl groups having 1 to 3 carbon atoms) An organic nonlinear optical material comprising an N,N-dimethylaniline derivative.