JPH0232064A - Liquid crystal compound - Google Patents

Abstract

NEW MATERIAL:Phenylpyridazine compounds of formula I (R* is alkyl having asymmetric carbon atom; R<2> is straight chain alkyl) in which the phenyl group is substituted through an oxygen atom by an alkyl group having an asymmetric carbon atom. EXAMPLE:(S)-3-Hexyl-6-[4-(6-methyloctyloxy)phenyl]pyridazine. USE:Liquid crystal compounds useful for forming various displays utilizing electro- optical properties thereof. The subject compounds either show ferroelectric chiral smectic phase in themselves or can be used as a chiral dopant even in case of the absence of the chiral smectic C phase because the compound can make another liquid crystal material show chiral smectic C phase by using as a doping material. PREPARATION:As shown by the reaction formula, a compound of formula II (R' is methyl, etc.) is used as the raw material and reacted with a compound of formula III and the objective compound of formula I is obtained via several processes.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a liquid crystal compound, particularly a phenylpyridazine compound in which an alkyl group having an asymmetric carbon atom is substituted with a phenyl group via an oxygen atom. The provided compounds are used to make various display devices utilizing their electro-optical properties.

(Prior art) Regarding liquid crystal compounds having a phenylpyridazine skeleton,
A compound in which an alkoxy group is substituted at the 3-position of a pyridazine ring and an alkoxy group is substituted at the 4-position of a benzene ring which is substituted at the 6-position is known as a liquid crystal material having a smectic C phase. (z,,chem,,,vol,17,334
(1977)) *It also has a phenylpyridazine skeleton, with 2-methylbutyroxy or 1-methylhebutyloxy substituted at the 3-position of the pyridazine ring, and a linear alkyl or alkoxy group substituted at the 4-position of the benzene ring. It has been reported that when two or more compounds are mixed together, a composition exhibiting the Sc phase is obtained.
．． ). Furthermore, it is also known that compounds in which hexyloxy, octyloxy, etc. are substituted at the 4-position of F do not have an intermediate phase (Mo1.Crys+7, Li
q, Cryst, Vol. 25.1986) As mentioned above, it is no exaggeration to say that the relationship between the chemical structure and performance of liquid crystal compounds is hardly clear. Determining performance is difficult. Under these circumstances, efforts are being made to create new compounds, investigate their performance, and find even better ones. (The point to be solved by the present invention) The present invention provides novel liquid crystal compounds that have a ferroelectric chiral smectic phase by themselves or which do not have a ferroelectric chiral smectic phase by themselves but are useful as chiral dopants. The present invention provides certain novel compounds.

(Means for Solving Problems) The compound provided by the present invention is synthesized as follows.

(R' is a group that can be left off later, such as methyl, benzyl, anisyl, benzoyl, acetyl, etc., R2 clam is a straight chain alkyl group, and R is an alkyl group with an asymmetric carbon.) Friedel-Crafts reaction is a chlorination reaction. It is carried out in solvents such as dichloroethane, trichloroethane, chloroform, etc. using catalysts such as aluminum, borax trifluoride, etc. Next, aliphatic linear aldehydes such as pentanal, hexanal, heptanal, octanal, nonanal, and decanal are reacted. The reaction is carried out in alcohol using sodium carbonate or potassium carbonate and an amine and an onium (eg, alkyl halide, benzyl halide, etc.) of 5-(2-hydroxyethyl)-4-methyl-1,3-thiazoline. After reacting the obtained compound with a diamine, it is dehydrogenated, and R' is eliminated by a suitable method depending on the type of R' (for example, hydrogen bromide-acetic acid, hydrolysis, hydrolysis, etc.).

The thus obtained compound represented by the formula (■) and optically active 2-methylethyl alcohol, 3-methylpentyl alcohol, 4-methylhexyl alcohol, 5-methylheptyl alcohol, and 6-methyl having an asymmetric carbon atom in the molecule Octyl alcohol, 7-methylnonyl alcohol,
8-methyldecanyl alcohol, 9-methylundecanyl alcohol, 1-methylheptyl alcohol, 2-methyloctyl alcohol, etc. are converted to the corresponding halides, or reacted with toluenesulfonyl chloride or methanesulfonyl chloride to produce sulfonic acids. Dimethylformamide by converting it to an ester.

The reaction is carried out using an alkali metal such as sodium hydride, sodium amide, potassium carbonate, sodium hydroxide, potassium hydroxide, etc. in an appropriate solvent such as dimethyl sulfoxide, benzene, toluene, dichloroethane, dioxane, or tetrahydrofuran.

Compound (2) provided by the present invention is thus obtained.

The resulting compound itself has chiral smectic C
(SrrrC) phase or not Lt S m♂ phase can be used as a doping material to make another liquid crystal material take SJC phase. It can be used as a ferroelectric chiral smectic liquid.

Gain is 0.8g 522.1260,8;15 do.

Example 1 Synthesis of (S)-3-hexyl-6-(4-(6-methyloctyloxy)phenyl)pyridazine Sodium 11 hydride (60%) 18 in dimethylformamide
6 mg, followed by 1.66 K of 4-(6-Hxyl-3-pinonyl)phenol. After stirring for 30 minutes, (S)-6-methyloctatool 1-silane h1. ．． 93 g was dissolved in 2 ml of dimedylformamide and added dropwise. The reaction was carried out at 80°C for 8 hours. After the reaction was completed, the reaction mixture was poured into ice water and extracted with ethyl acetate.

The organic layer was washed with water, dried, and then concentrated under reduced pressure. Silica gel column chroma of the obtained reaction product! - Graphography and recrystallization to yield the title compound 8.02. d,
2) -17,67,d, IH7゜27,d,
1N-I 6. 98. d, 2H4゜00゜t, 2H2,98,t, 2NI
O, 60-2.10, m, 2811 Example 277 Synthesis of (S) 3-octyl-6[4(4-methylhexyloxy)phenylcopyridazine: 4-(6-octyl-3-pyridazine) 0.85g of (S)phenol and (S)
The title compound was obtained in the same manner as in Example using 1-0.76 of -4-methylhexanol. Amount of hot water: 0.5g 522°1-258.

1,, O35.

8.02° 27, d.

L, 2I1 1.6. m.

d, 2I-I 7.69. d, IH7゜1
B1 6. 99. d, 2LI 4.
00°2.98. t, 2H0,60~2゜2
8 I-I The phase transition temperature (°C) of the compound of each Example was 6 (°C). The following compounds were synthesized according to the method of Example, using the corresponding raw materials as shown below.

Example 7: “cry-Otsu L”, Is.

Example 8” CrylIs.

Example 9: CrynIs.

(1:1wt) (The phase diagram when the compound of Example 7 or the compound of Example 9 is mixed at the phase transition temperature is shown below.

A: Example 7 compound (10° 1: 1wt) A: Example 9 compound (10: 1wt) A: Example 1 compound (10:1wt) A: Example 3 compound (10:1wt)

Claims (1)

[Claims] Formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R^* is an alkyl group having an asymmetric carbon atom, R^2
indicates a straight-chain alkyl group)