JPH05294950A - 6-(2'-@(3754/24)2'-furil)-vintl)methylene-6,7,8,9-tetrahydro-5h-benzocyclohepten-5-one and non-linear optical material - Google Patents

Abstract

PURPOSE:To provide the subject new compound useful as a non-linear optical material exhibiting a remarkable non-linear optical property in the field of optical communication. CONSTITUTION:A compound of the formula. This compound is obtained, e.g. by heating and refluxing 3-(2-furil)acrolein and 6,7,8,9-tetrahydro-5H- benzocyclohepten-5-one in the presence of an alkaline catalyst in a solvent such as methanol. Useful as a non-linear optical material important in a light signal processing system such as optical parametric oscillation, generation of harmonic or light switch. Since the compound of the formula has a carbonyl group as an acceptor group conjugated with styryl pi electrons, a large dipole moment is produced by charge transfer in an excited state. Thereby, the compound has a high hyperpolarizability and a remarkable nonlinear optical effect can be consequently obtained.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an optical parametric oscillation,
Novel 6- used for important nonlinear optical materials in optical signal processing systems such as harmonic generation and optical switching
[2 '-(2 "-furyl) -vinyl] methylene-6,
The present invention relates to 7,8,9-tetrahydro-5H-benzocyclohepten-5-one and a non-linear optical material using this compound.

[0002]

2. Description of the Related Art Nonlinear optical materials, which are considered to play an important role in the fields of optical communication and the like, exhibit functions such as optical mixing, parametric oscillation, and generation of optical harmonics based on the nonlinear response of materials. , Conventionally, KH ₂ PO ₄ , NH ₄ H ₂
Inorganic crystals such as PO ₄ have been used. However, these materials have not met the aforementioned requirements because of their deliquescent properties, low non-linear susceptibility and low fracture threshold. In addition, the primary and secondary electro-optic effects that can be used for optical switching are essentially the same nonlinear polarization effects as the secondary and tertiary nonlinear optical effects, respectively, so basically the same materials may be used. There is. Since the response speed of the inorganic material is slow, the frequency band is narrowed. Organic nonlinear optical materials utilizing polarization of π-electron system are widely researched in various fields, because their nonlinear optical constants are larger than inorganic materials, and generally they are excellent in that they have no deliquescent property and have a high threshold for destruction. Development is in progress. Regarding recent achievements, for example, "Nonlinear Optical Properties of Organic Molecule and Crystals" (Nonlinea)
r Optical Properties of O
rganic molecules and crys
tals) Vol. 1 and Vol. 2, D. S. Che
mla, J.M. Edited by Zyss (1987 Academic)
(Published by Press).

However, a material such as a semiconductor laser having a non-linear optical constant large enough to achieve a purpose with a low-power laser has not been found, and further development of a new material is strongly demanded.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a novel compound as a nonlinear optical material having a large nonlinear optical constant and a nonlinear optical material using the same.

[0005]

The present invention provides 6- [2 '-(2 "-furyl) -vinyl] methylene-6,7,8,9-tetrahydro-5H-benzocyclo of the formula [I]. The present invention relates to hepten-5-one, a non-linear optical material composed of this compound, and a non-linear optical material composed of a composition containing this compound.

[Chemical 2]

6-in the formula [I] according to the present invention
[2 '-(2 "-furyl) -vinyl] methylene-6,
7,8,9-Tetrahydro-5H-benzocyclohepten-5-one is, for example, 3- (2-furyl) acrolein and 6,7,8,9-tetrahydro-5H-benzocycloheptene-5-one. The on can be synthesized by heating under reflux in a solvent such as methanol in the presence of an alkali catalyst.

The nonlinear optical material according to the present invention is 6- [2 '-(2 "-furyl) -vinyl] methylene-6,7,8,9-tetrahydro-5H represented by the above formula [I].
-Benzocyclohepten-5-one may be used alone or a composition in which this compound is dispersed or dissolved in a polymer compound. As a polymer compound,
For example, methyl (meth) acrylate (indicating methacrylate or acrylate; the same applies hereinafter), ethyl (meth) acrylate, n-butyl (meth) acrylate,
Cyclohexyl (meth) acrylate, (meth) acrylic acid, styrene, vinyltoluene, divinylbenzene,
Homopolymers, copolymers or terpolymers of monomers such as vinyl chloride and β-vidroxyethyl (meth) acrylate, polyesters, polyamides, polyurethanes, polycarbonates, cellulose esters and polyethers are used. The compound represented by the formula [I] and the corresponding monomer may be mixed and then polymerized by the action of heat or light to obtain a composition, and the above polymer compound and the compound represented by the formula [I] are appropriately used. The composition may be obtained by dissolving and mixing with a suitable solvent and then removing the solvent. In the former case, by poling during polymerization,
Alternatively, both the former and the latter can improve the non-linear optical performance by performing poling after obtaining the composition. Alternatively, in the presence of a DC electric field, the compound of the above formula [I] is heated to a temperature equal to or higher than the melting point and melted, and then slowly cooled or rapidly cooled while maintaining the electric field, thereby controlling the alignment state of the molecules. It is also possible to obtain a high-performance single crystal or molecular glass.

The above-mentioned non-linear optical materials can be used in the form of bulk crystals independently, or in fiber type, slab type, plane type,
It can be used as a part of a waveguide type optical element such as a channel type. Examples of the nonlinear optical element using the above nonlinear optical material include a wavelength conversion element using the second harmonic generation, sum frequency generation or optical parametric oscillation, a phase modulation element using the electro-optic effect, a polarization plane modulation element and the like. ..

[0009]

The compound of the present invention has a carbonyl group as an acceptor group, and these are conjugated with a styryl π electron system, so that a large dipole moment occurs due to the charge transfer in the excited state, and the compound has a high hyperpolarizability. Therefore, a high nonlinear optical effect can be obtained.

[0010]

EXAMPLES The present invention will be described in more detail by way of examples. 6- [2 '-(2 "-furyl) -vinyl] methylene-
Synthesis of 6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one 3- (2-furyl) acrolein 0.762 g (6.2
5 mmol), 6,7,8,9-tetrahydro-5H-
Benzocycloheptan-5-one 1 g (6.25 mmo
l) 5 ml of methanol and 0.5 ml of 35% NaOH aqueous solution were placed in a 50 ml eggplant-shaped flask, a piece of zeolite was added, and the mixture was heated under reflux for about 1 hour with a condenser for cooling. Crystals came out when left to cool, so this was filtered and washed thoroughly with methanol. The yield is about 1.548 g (82
%)Met. The structure of the product was confirmed by nmr and absorption spectrum. The UV-visible absorption spectrum of a methylene chloride solution of this compound is shown in FIG.
The r spectrum is shown in FIG.

Comparative Example, Example 6- [2 '-(2 "-furyl) -vinyl] methylene-
Absorption maximum wavelength (λ _max , methylene chloride solution) of 6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one and second harmonic generation efficiency (SHG efficiency, urea Table 1 shows the second harmonic intensity ratio (when the case is 1) and the melting point. The powder method is outlined in Journal of Applied Physics (Journa).
l of Applied Physics) Vol.
36 (1963) pp. 3798-3813. Sample powder classified to a particle size of 50 to 150 μm is sandwiched between non-fluorescent slide glass (Matsunami glass),
Spectro Laser System pulse Nd: YAG laser (SL303 type, maximum output 850mJ, half width 15n
s, output per pulse 60 MW, beam diameter 9.5 m
m, wavelength 1.064 μm, repetition frequency 10 Hz). The intensity of the generated second harmonic of 532 nm was measured by a photomultiplier tube through an infrared filter and a UV filter.

[0012]

[Table 1]

[0013]

INDUSTRIAL APPLICABILITY With the novel compound according to the present invention, a nonlinear optical material having high optical nonlinearity can be obtained.

[Brief description of drawings]

FIG. 1 shows 6- [2 ′-(2 ″ -furyl) -obtained in Examples.
Vinyl] methylene-6,7,8,9-tetrahydro-5
It is an ultraviolet-visible absorption spectrum of a methylene chloride solution of H-benzocyclohepten-5-one.

FIG. 2 shows 6- [2 ′-(2 ″ -furyl) -obtained in Examples.
Vinyl] methylene-6,7,8,9-tetrahydro-5
It is a nmr spectrum of a deuterated chloroform solution of H-benzocyclohepten-5-one.

Claims (3)

[Claims] 1. A 6- [2 ′-(2 ″) represented by the formula [I].
-Furyl) -vinyl] methylene-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one. [Chemical 1] 2. 6- [2 '-(2 "-furyl) -vinyl] methylene-6,7,8,9-tetrahydro-5H-
A non-linear optical material composed of benzocyclohepten-5-one. 3. 6- [2 '-(2 "-furyl) -vinyl] methylene-6,7,8,9-tetrahydro-5H-
A non-linear optical material comprising a composition containing benzocyclohepten-5-one.