JPH0616611A - Alpha-cyanocinnamic acid ester compound and organic nonlinear optical material comprising the compound - Google Patents

Abstract

PURPOSE:To provide a new alpha-cyanocinnamic acid ester compound greatly high in a SHG effect, important as an organic nonlinear optical material excellent in transparency, and also important as a color-generating material and a laser dyestuff because of generating large fluorescent light. CONSTITUTION:A compound of formula I (D is group of formula II-V; R is CH3, C2H5, C3H7, C4H9) e.g. methyl alpha-cyano-p-[(R)-2- phenylpropylamido]cinnamate. The compound is obtained by reacting an optically active carboxylic acid with methyl alpha-cyano-p-aminocinnamate which is synthesized by the condensation reaction of methyl cyanoacetate with p- aminobenzaldehyde. The compound is characterized by having the same ultra- molecular degree of polarization (beta) as 2-methyl-4-nitroaniline which is a typical nonlinear optical material and simultaneously by having excellent transparency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel organic compound, and more specifically to an organic nonlinear optical material used as a light control element in a wide range of fields such as optical computer and optical communication, which has SHG activity, The present invention relates to an α-cyanocinnamic acid ester compound having good transparency and an organic nonlinear optical material comprising the compound.

[0002]

2. Description of the Related Art Non-linear optical materials cause phenomena such as frequency conversion, amplification, oscillation and switching of laser light.
It can be applied to harmonic generation (SHG), third harmonic generation (THG), high-speed shutter, optical memory, optical operation element, and the like. As described above, the nonlinear optical material has a function of converting the optical frequency, and since it can be applied to an optical switch or the like that takes advantage of the property that the refractive index changes with an electric field, active research is underway. Has been.

Since the origin of the nonlinearity is intramolecular π-electrons in the organic nonlinear optical material, lattice vibration does not accompany the optical response, and therefore the response is faster than the inorganic material and the nonlinear optical constant is large. It is possible to synthesize an object or an object whose absorption region can be changed. Moreover, the method for forming a material element is not limited to single crystallization, and various methods such as an LB film, a vapor deposition method, a liquid crystal, and a polymer are conceivable.

Regarding recent research results on nonlinear optical materials, see, for example, “Nonlinear Optical P”.
properties of Organic Mole
cules and Crystals Vol. I
And Vol. II "D. S. CHEMLA, J .; ZY
SS (Academic Press, 1987
The latest research status is summarized in literatures such as "Yearbook", "Organic Nonlinear Optical Materials" by Shinsuke Umegaki (Bunshin Publishing Co., Ltd., 1990).

By the way, among the nonlinear optical effects required as the nonlinear optical material, particularly the second harmonic generation (SH
G) is positioned as a basic technology for wavelength conversion, and a material having a large nonlinear optical constant is required for efficient SHG. Then, as described in detail in the above-mentioned literature, in order to exhibit SHG activity, it is necessary that the crystal does not have a center of symmetry, that is, the inversion symmetry does not occur in the molecular arrangement in the crystal. . So far
The following general formula [II]

[0006]

[Chemical 6]

[Wherein, D _{1 to} D ₅ are -C
_{H 3, -C 2 H 5,} -OCH 3, -OC 2 H 5, -N
(CH _{3) 2,} shows a _{-N (C 2 H 5) 2} , X, Y, Z
Is indicative -CN, -COOR, a -NO _2. ]
Although the styrene derivative represented by is well known, these known compounds have a relatively large nonlinear susceptibility β, but easily form a crystal having central symmetry, and the crystal does not necessarily have a nonlinear effect. . Further, the following compound (Japanese Patent Laid-Open No. 63-221327) has the general formula

[0008]

[Chemical 7]

4-dimethylamino-β-cyano-β-methoxycarbonylstyrene represented by the formula: is known.
This compound is known to have a non-linear effect that is 10 times higher than that of urea, but has a maximum absorption wavelength of 427 nm in a long wavelength region, and has properties that are not preferable as a wavelength conversion material. Further, this compound is a compound having SHG activity, but since the dipole becomes large, the absorption wavelength tends to be in the long wavelength region. Therefore, it is difficult to provide a material having high SHG efficiency and excellent blue to green light transmittance.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an organic nonlinear optical material that overcomes the problems of the prior art and is stable at room temperature and excellent in optical damage resistance. As a result of earnest studies, the present inventors have found that a series of α-cyano-p-amide cinnamic acid ester compounds having a cinnamic acid ester structure and having an optically active substituent having no inversion symmetry in the molecule The inventors have found that they meet the above-mentioned purposes and completed the present invention.

[0011]

The present invention is an α-cyanocinnamic acid ester compound represented by the following general formula [I].

[0012]

[Chemical 8] However, in general formula [I], the meaning of each symbol is as follows. D:

[0013]

[Chemical 9]

[0014]

[Chemical 10]

[0015]

[Chemical 11]

[0016]

[Chemical 12] _{R: -CH 3, -C 2 H} 5, -C 3 H 7 -C 4 H 9

The present invention is also an organic nonlinear optical material comprising the above-mentioned α-cyanocinnamic acid ester compound. Hereinafter, the present invention will be described in detail. The compounds represented by the general formula [I] are compounds having a relatively large π-electron conjugated system, an amide group as an electron-donating group, and a cyano group and an alkoxycarbonyl group as an electron-withdrawing group. .

These compounds are characterized by having a supramolecular polarizability (β) equivalent to that of 2-methyl-4-nitroaniline (MNA), which is a typical non-linear optical material, while being excellent in transparency. It is a material to do. Further, as shown in the above general formula, the asymmetric carbon is bonded to the amide group, so that the molecule itself has asymmetry. Therefore, it is considered that the inversion symmetry of the crystal was broken and SHG was expressed.

These compounds can be obtained by reacting an optically active carboxylic acid with methyl α-cyano-p-aminocinnamate synthesized by a condensation reaction of cyanoacetic acid methyl ester and p-aminobenzaldehyde. These compounds have excellent transparency (λmax = 348 to 354).
nm), which has a large SHG efficiency of 46 times that of urea, shows a very excellent nonlinear optical effect.

The crystals of these compounds are thermally stable, less susceptible to optical damage, and easy to process, so that they can be easily made into devices. These compounds can be used as non-morphic optical materials in various forms such as powder, single crystal, and solution.

[0021]

EXAMPLES The present invention will be specifically described below with reference to examples, but needless to say, the present invention is not limited to these examples. Example 1 α-Cyano-p-[((R) -2-phenylpropyl)
Amido] methyl cinnamate and α-cyano-p-
[((S) -2-Phenylpropyl) amide] Cinnamic acid methyl ester

[0022]

[Chemical 13]

(Synthesis of methyl (ethyl) α-cyano-p-aminocinnamate) To 6.0 ml of methyl cyanoacetate, 10 drops of piperidine and 300 benzene (or ethanol) were added.
The reaction was performed for 10 hours while adding ml and extracting 4.8 g of a commercially available p-aminobenzaldehyde monomer (containing 50% homopolymer manufactured by Tokyo Kasei) while refluxing at an oil temperature of 100 (or 85) ° C. After the reaction was completed, the precipitated crystals were washed with methanol and dried in vacuum to obtain α-cyano-
3.4 g of methyl p-aminocinnamate was obtained.

In this reaction, when ethyl cyanoacetate is used instead of methyl cyanoacetate, ethyl α-cyano-p-aminocinnamate can be obtained. α-cyano-p
-Methyl aminocinnamate melting point, IR, UV and NMR
The measurement results of are collectively shown.

[0025]

[Chemical 14]

Melting point: 212 [° C.] IR (KBr): 3480, 3370 (Ar-NH
₂ ), 2230 (-CN), 1730 (-CO-O
-), 1580 (Ar-C = C) [cm < ^-1 >] UV (EtOH): [lambda] max = 406 [nm] < ¹ > H-NMR (DMSO): [delta] = 3.78 (s, 3H), 6.
65 (d, 2H), 6.72 (s, 2H), 7.83
(D, 2H), 8.01 (s, 1H) [ppm]

(Production of methyl α-cyano-p-[((R) -2-phenylpropyl) amide] cinnamate) 2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, (R)-(-)- 2 phenylpropionic acid 1.50g, tetrahydrofuran (THF) 30m
1 was added, and the mixture was stirred at room temperature for 2 hours. This solution, 0 ℃
About 200 ml of a THF solution of methyl α-cyano-p-aminocinnamate (2.0 g) was slowly added to the mixture while cooling to room temperature and stirring. The solution was refluxed for 3 hours and then allowed to cool to room temperature.

An oily substance was obtained by filtering the precipitate and distilling off the solvent. When an appropriate amount of methanol was added to this, yellow crystals were precipitated. The crystals were filtered and dried, and then recrystallized from ethyl acetate-hexane to obtain the desired product, α-cyano-p-[((R) -2-phenylpropyl) amido] cinnamate.

Α-Cyano-p-[((R) -2-phenylpropyl) amide] methyl cinnamate melting point, IR, UV
And the measurement results of NMR are collectively shown. Melting point: 203 [° C] IR (KBr): 2240 (-CN), 1720
(-CO-O-), 1700 (-CO-NH-) 1580 (Ar-C = C) [cm- ¹ ] UV (EtOH) :? max = 354 [nm] NMR (DMSO):? = 1.44. (D, 3H), 3.
84 (s, 3H) 3.89 (q, 1H), 7.24 (t, 1H) 7.34 (t, 2H), 7.40 (d, 2H) 7.81 (d, 2H), 8 0.04 (d, 2H) 8.28 (s, 1H) 10.5 (s, 1H) [ppm]

Further, the obtained α-cyano-p-
[((R) -2-Phenylpropyl) amide] Microcrystalline powder of methyl cinnamate was added to Nd: YAG laser (wavelength = 1.
Upon irradiation with 064 μm and an output of 10 mJ / pulse, a second harmonic was generated (SHG), and green light with a wavelength (532 nm) that was ½ of the incident light could be observed. The SHG effect is
It was 44 times that of urea. In addition, α-cyano-p-[((S) -2-phenylpropyl) obtained by the same method
Amide] The SHG efficiency of the microcrystalline powder of methyl cinnamate was 46 times that of urea.

These crystals were stable at room temperature, excellent in transparency, and no optical damage was observed. Further, methyl α-cyano-p-[(2-phenylpropyl) amido] cinnamate, which is a racemate of this compound, was synthesized and its SHG efficiency was evaluated. No activity was observed.

[Example 2] α-cyano-p-[((R) -2-phenylpropyl)
Amide] Ethyl cinnamate

[0033]

[Chemical 15]

30 ml of tetrahydrofuran was added to 2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, and 1.50 g of (R)-(-)-2phenylpropionic acid, and the mixture was stirred at room temperature for 2 hours. . This solution was cooled to 0 ° C. and stirred while stirring in Example 1.
Ethyl α-cyano-p-aminocinnamate (2.
About 50 ml of a THF solution of 0 g) was slowly added. This solution was reacted at 50 ° C. for 3 hours and then allowed to cool to room temperature.

The precipitate was filtered and the solvent was distilled off to obtain an oily substance. When an appropriate amount of ethanol was added to this, yellow crystals were precipitated. The crystals were filtered and dried, and then recrystallized from ethyl acetate-hexane to obtain the desired product, α-cyano-p-[((R) -2-phenylpropyl) amido] cinnamate.

Α-Cyano-p-[((R) -2-phenylpropyl) amido] ethyl cinnamate melting point, IR, UV
And the measurement results of NMR are collectively shown. Melting point: 147 [° C] IR (KBr): 2240 (-CN), 1725
(-CO-O-), 1710 (-CO-NH-) 1600 (Ar-C = C) [cm- ¹ ] UV (EtOH): [lambda] max = 353 [nm] < ¹ > H-NMR (DMSO): [delta] =. 1.30 (t, 3H), 1.
43 (d, 3H) 3.87 (q, 1H), 4.30 (q, 2H) 7.26 (t, 1H), 7.34 (t, 2H) 7.40 (d, 2H), 7 .81 (d, 2H) 8.04 (d, 2H), 8.26 (s, 1H) 10.5 (s, 1H) [ppm]

Further, the obtained α-cyano-p-
[((R) -2-Phenylpropyl) amide] fine crystal powder of ethyl cinnamate was converted into Nd: YAG laser (wavelength = 1.
Upon irradiation with 064 μm and an output of 10 mJ / pulse, a second harmonic was generated (SHG), and green light with a wavelength (532 nm) that was ½ of the incident light could be observed. The SHG effect is
It was 0.01 times that of urea. This crystal was stable at room temperature, had excellent transparency, and showed no optical damage.

[Example 3] α-cyano-p-[((S) -2-methoxybenzyl)
Amide] Methyl cinnamic acid

[Chemical 16]

30 ml of tetrahydrofuran was added to 2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, and 1.50 g of (S)-(+)-α-methoxyphenylacetic acid, and the mixture was stirred at room temperature for 2 hours. . This solution was cooled to 0 ° C. and stirred while stirring in Example 1.
Methyl α-cyano-p-aminocinnamate (2.
About 100 ml of a THF solution of 0 g) was slowly added. This solution was reacted at 50 ° C. for 3 hours and then allowed to cool to room temperature.

An oily substance was obtained by filtering the precipitate and distilling off the solvent. When an appropriate amount of ethanol was added to this, yellow crystals were precipitated. The crystals were filtered and dried, and then recrystallized from ethyl acetate-hexane to obtain the desired product, α-cyano-p-[((S) -2-methoxybenzyl) amido] cinnamate.

Methyl α-cyano-p-[((S) -2-methoxybenzyl) amido] cinnamate, IR, UV
And the measurement results of NMR are collectively shown. Melting point: 183 [° C] IR (KBr): 2250 (-CN), 1740
(-CO-O -), 1710 (-CO-NH-) 1610 (Ar-C = C) [cm -1] UV (EtOH): λmax = 348 [nm] 1 H-NMR (DMSO): δ = 3.38 (s, 3H), 3.
85 (s, 3H) 4.91 (s, 1H), 7.38 (t, 1H) 7.40 (t, 2H), 7.49 (d, 2H) 7.91 (d, 2H), 8 .04 (d, 2H) 8.30 (s, 1H) 10.5 (s, 1H) [ppm]

Further, the obtained α-cyano-p-
[((S) -2-Methoxybenzyl) amido] fine crystal powder of methyl cinnamate was converted into Nd: YAG laser (wavelength = 1.
Upon irradiation with 064 μm and an output of 10 mJ / pulse, a second harmonic was generated (SHG), and green light with a wavelength (532 nm) that was ½ of the incident light could be observed. The SHG effect is
It was 0.01 times that of urea. This crystal was stable at room temperature, had excellent transparency, and showed no optical damage.

Example 4 α-Cyano-p-[((S) -2-methoxybenzyl)
Amide] Ethyl cinnamate

[Chemical 17]

To 2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, and 1.50 g of (S)-(+)-α-methoxyphenylacetic acid, 30 ml of tetrahydrofuran was added, and the mixture was stirred at room temperature for 2 hours. . This solution was cooled to 0 ° C. and stirred while stirring in Example 1.
Ethyl α-cyano-p-aminocinnamate (2.
About 50 ml of a THF solution of 0 g) was slowly added. This solution was reacted at 50 ° C. for 3 hours and then allowed to cool to room temperature.

The precipitate was filtered and the solvent was distilled off to obtain an oily substance. When an appropriate amount of ethanol was added to this, yellow crystals were precipitated. The crystals were filtered and dried, and then recrystallized from ethyl acetate to obtain the desired product α-cyano-p-[((S) -2-methoxybenzyl) amide].
Obtained ethyl cinnamate.

Α-Cyano-p-[((S) -2-methoxybenzyl) amido] ethyl cinnamate melting point, IR, UV
And the measurement results of NMR are collectively shown. Melting point: 134 [° C] IR (KBr): 2250 (-CN), 1740
(-CO-O -), 1710 (-CO-NH-) 1610 (Ar-C = C) [cm -1] UV (EtOH): λmax = 348 [nm] 1 H-NMR (DMSO): δ = 1.30 (t, 3H), 3.
38 (s, 3H) 4.31 (q, 3H), 4.91 (s, 1H) 7.35 (t, 1H), 7.40 (t, 2H) 7.50 (d, 2H), 7 .92 (d, 2H) 8.04 (d, 2H), 8.29 (s, 1H) 10.5 (s, 1H) [ppm]

Further, the obtained α-cyano-p-
[((S) -2-Methoxybenzyl) amide] fine crystal powder of ethyl cinnamate was converted into Nd: YAG laser (wavelength = 1.
Upon irradiation with 064 μm and an output of 10 mJ / pulse, a second harmonic was generated (SHG), and green light with a wavelength (532 nm) that was ½ of the incident light could be observed. The SHG effect is
It was 0.06 times that of urea. This crystal was stable at room temperature, had excellent transparency, and showed no optical damage.

Example 5 Methyl α-cyano-p-[((S) -2-methylbutyl] cinnamate

[Chemical 18]

2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, (S)-(+)-2-
To 1.00 g of methyl butyric acid, tetrahydrofuran (TH
F) 30 ml was added, and the mixture was stirred at room temperature for 2 hours. This solution was cooled to 0 ° C. and stirred, and the α-cyano-p-aminomethylcinnamate (2.0 g) obtained in Example 1 (2.0 g) was dissolved in T.
About 50 ml of HF solution was added slowly. 50 this solution
After reacting for 3 hours at ℃, it was allowed to cool to room temperature.

The precipitate was filtered and the solvent was distilled off to obtain an oily substance. When an appropriate amount of ethanol was added to this, yellow crystals were precipitated. The crystals were filtered and dried, and then recrystallized from ethyl acetate-hexane to obtain the desired product, methyl α-cyano-p-[((S) -2-methylbutyl) amido] cinnamate.

The melting point of methyl α-cyano-p-[((S) -2-methylbutyl) amide] cinnamate, IR, UV and NMR measurement results are shown together. Melting point: 146 [° C] IR (KBr): 2250 (-CN), 1740
(-CO-O -), 1720 (-CO-NH-) 1610 (Ar-C = C) [cm -1] UV (EtOH): λmax = 353 [nm] 1 H-NMR (DMSO): δ = 0.86 (t, 3H), 1.
05 (d, 3H) 1.42 (m, 1H), 1.63 (m, 1H) 2.46 (m, 1H), 3.85 (s, 3H) 7.83 (d, 2H), 8 0.05 (d, 2H) 8.29 (s, 1H) 10.4 (s, 1H) [ppm]

Further, the obtained α-cyano-p-
[((S) -2-Methylbutyl) amide] fine crystal powder of methyl cinnamate was added to Nd: YAG laser (wavelength = 1.06).
When irradiated with 4 μm and an output of 10 mJ / pulse, a second harmonic wave is generated (SHG), and a half wavelength of the incident light (53
2 nm) green light could be observed. The SHG effect was 0.06 times that of urea. This crystal is stable at room temperature,
It was excellent in transparency and no light damage was observed.

Example 6 Methyl α-cyano-p-[((S) -2-methoxy-2- (trifluoromethyl) benzyl) amide] cinnamate

[Chemical 19]

2.62 g of triphenylphosphine, 10 ml of bromotrichloromethane, (S)-(-)-α-
To 2.0 g of methoxy-α- (trifluoromethyl) phenylacetic acid, 30 ml of tetrahydrofuran (THF)
Was added and the mixture was stirred at room temperature for 2 hours. This solution was cooled to 0 ° C. and stirred while the α-cyano-obtained in Example 1 was obtained.
A solution of methyl p-aminocinnamate (2.0 g) in THF about 1
00 ml was added slowly. This solution was reacted at 50 ° C. for 3 hours and then allowed to cool to room temperature. An oily substance was obtained by filtering the precipitate and distilling off the solvent. When an appropriate amount of methanol was added to this, yellow crystals were precipitated.
The crystals were filtered and dried, and then recrystallized from ethyl acetate-hexane to obtain α-cyano-p-[((S)-
2-methoxy-2- (trifluoromethyl) benzyl)
Amide] Methyl cinnamate was obtained.

The melting points of methyl α-cyano-p-[((S) -2-methoxy-2- (trifluoromethyl) benzyl) amide] cinnamate, IR, UV and NMR measurement results are shown together. Melting point: 168 [° C] IR (KBr): 2230 (-CN), 1730
(-CO-O-), 1710 (-CO-NH-) 1600 (Ar-C = C) [cm < ^-1 >] UV (EtOH): [lambda] max = 344 [nm] < ¹ > H-NMR (DMSO): [delta] =. 3.58 (s, 3H), 3.
86 (s, 3H) 7.48 (m, 3H), 7.57 (t, 2H) 7.95 (d, 2H), 8.34 (s, 1H) 10.6 (s, 1H) [ppm ]

Further, the obtained α-cyano-p-
[((S) -2-Methoxy-2- (trifluoromethyl) benzyl) amide] N-methyl fine crystal powder
d: YAG laser (wavelength = 1.064 μm, output 10
When irradiated with mJ / pulse, the second harmonic is generated (SH
G), and green light having a wavelength (532 nm) half that of the incident light could be observed. The SHG effect was 0.01 times that of urea. This crystal was stable at room temperature, had excellent transparency, and showed no optical damage.

[0057]

INDUSTRIAL APPLICABILITY The α-cyano-p-amide cinnamic acid ester compound of the present invention is an organic nonlinear optical material having extremely high SHG efficiency and excellent transparency. Particularly, in Example 1, introduction of an optically active functional group was shown to be an effective means for obtaining an excellent nonlinear optical material. Further, since the α-cyano-p-amide cinnamic acid ester compound shows a large fluorescence, it is also important as a light emitting material and a laser dye.

Claims (2)

[Claims] 1. An α-cyanocinnamic acid ester compound represented by the following general formula [I]. [Chemical 1] However, in general formula [I], the meaning of each symbol is as follows. D: [Chemical 2] [Chemical 3] [Chemical 4] [Chemical 5] _{R: -CH 3, -C 2 H} 5, -C 3 H 7, -C 4 H 9 2. An organic nonlinear optical material comprising the α-cyanocinnamic acid ester compound according to claim 1.