GB2125043A - Liquid crystal dicyanophenyl biphenylcarboxylic esters - Google Patents
Liquid crystal dicyanophenyl biphenylcarboxylic esters Download PDFInfo
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- C09K19/08—Non-steroidal liquid crystal compounds containing at least two non-condensed rings
- C09K19/10—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings
- C09K19/20—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers
- C09K19/2007—Non-steroidal liquid crystal compounds containing at least two non-condensed rings containing at least two benzene rings linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters or ethers the chain containing -COO- or -OCO- groups
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Abstract
Nematic liquid crystal biphenyl esters have the formula (1> <IMAGE> in which R<1> is hydrogen or an alkyl-, alkoxy-, or alkanoyloxy-group, whose carbon chain contains 1-12 carbon atoms and may be unbranched or branched and may contain a chiral centre; R<2> is an alkyl group with 1- 12 carbon atoms, whose carbon chain may be unbranched or branched and may contain a chiral centre; X<1> and X<2> are each hydrogen, fluorine, chlorine, bromine, or nitrile groups. Liquid crystal mixtures in accordance with the invention exhibit an overall negative dielectric anisotropy and contain at least one compound of the formula (1) as the nematic component of high negative dielectric anisotropy.
Description
SPECIFICATION
New biphenyl ester derivatives and liquid crystal mixtures thereof
The invention describes novel substituted biphenyl esters possessing stable nematic phases and of negative or very negative dielectric anisotropy for use in electro-optic displays. The invention also describes liquid crystal mixtures (LC mixtures) which contain the new compounds.
It is well known that for various types of displays, e.g., for the so-called "guest-host displays" (GHD) and the homeotropic-nematic displays (HND), nematic mixtures with negative values of AE are required. AE is the dielectric anisotropy (DA) and is defined as AE=E11-E1, where E11 represents the dielectric constant (DC) parallel to the molecular axis and E1 represents the dielectric constant perpendicular to the molecular axis.
To this end, according to the state of the art, a strongly polarising group, e.g. typically the nitrile function, is built into correspondingly anisotropic or nematic molecular structures, not in the direction of the molecular axis, but at an angle to it; typical examples of such compounds are described in DE OS26 13 293; 28 35 662; 28 36 086 and 28 53 728 as well as in Mol. Cryst. Liq. Cryst., 42, 139 (1977) by J. C. Dubois et al.
Furthermore, various nematic materials are known, which possess several such lateral substituents, e.g., typically two nitrite groups attached to the same ring or to different rings of the molecule, in order to produce more negative values of the dielectric anisotropy.
So the state of the art describes especially nematic or nematogenic compounds with typically two or three rings in the molecule, which are joined together by linkages, such as the covalent bond or the carboxy- or oxycarbonyl-groups. One of the rings is a benzene ring which bears two lateral nitrile functions. Examples of such dicyano-compounds are described in SU-PS 562 547, DE
OS 29 37 700 and in the European patent application, publication number 0 023 728. Such dicyanocompounds are not freely commercially available except in special cases. They also generally exhibit certain disadvantageous properties, namely pronounced photochemical and/or thermal instability.The known (but commercially unavailable) materials which incorporate two lateral nitrile groups in the same benzene ring and which are also suitable for commercial display devices, are relatively complicated to synthesise and necessitate long reaction pathways. They would, therefore, be relatively expensive to manufacture and may also possess further disadvantageous properties, such as insufficiently high nematic-isotropic liquid transition temperatures.
The objective of the invention is to specify novel substituted biphenyl esters with sufficiently high negative dielectric anisotropy and sufficiently stable nematic phases for liquid crystal display devices.
The new materials can be synthesised according to short reaction pathways from commercially available starting materials or easily preparable starting materials, suitable for commercial manufacture. However, the new material still possesses, despite the short reaction pathways, those desirable properties, such as general chemical, photo-chemical, electro-chemical, and thermal stability, responsible for the overall stability of the compounds in the nematic state, i.e., simply stated, the stability of the nematic phase.
A further objective of the invention is to specify mixtures of overall negative dielectric an isotropy, which contain at least one nematic material of high negative dielectric anisotropy, which exhibits the above mentioned advantages.
According to the invention these objectives can be achieved by the new biphenyl esters with formula (1)
In the formula (1) R' is a hydrogen atom or a C1~,2-alkyl-, C112-alkoxy-, or a C112-alkanoyloxy-group; the carbon-chains of the above mentioned groups can be normal or branched and which may contain a chiral centre in the latter case, i.e., they may contain an unsymmetrically substituted carbon atom.
Examples of the alkyl- or alkoxy-groups are those, whose carbon-chains are the following groups: methyl-, ethyl-, propyl-, butyl-, pentyl-, hexyl-, heptyl-, octyl-, nonyl-, decyl-, undecyl-, dodecyl-, or the corresponding carbon-chains containing a chiral centre: 1-methylpropyl-,1-methylbuty-,2- methylbutyl-, 1 -methylpentyl-, 2-methylpentyl-, 3-methylphenyl-, 1-, or 2-, or 3-, or 4-methylhexyl-, 1-, or 2-, or 3-, or 4-, or 5-methylheptyl, or another branched alkyl chain containing a chiral centre.
Examples of the alkanoyloxy groups, i.e., groups of the formula H2p+1 Cp(O)O, are those in which p is 1 to 11 for the carbon-chain which itself is one of the aforementioned examples, which contain up to eleven carbon atoms.
R2 is a C,~12-alkyl group, for instance one of the above mentioned examples for R1=alkyl.
The two rings of the biphenyl moiety, i.e., the benzene rings joined together by a covalent bond as linking unit, can, moreover, when required, bear a lateral polarising substituent; accordingly, as desired,
X1 and X2 may be hydrogen atoms, halogen atoms chosen from fluorine, chlorine, bromine, or nitrile functions. Preferably one of the groups X', X2 has another meaning than hydrogen. Fluorine is especially preferred as a means of lowering the melting points of the molecules of formula (1) without significantly altering or lowering the dielectric an isotropy of the molecules.
A biphenyl ester described in the invention which is suitable for many applications has the formula (2)
in which R3 and R4 are identical or different C,~12-alkyl groups with normal carbon-chains or branched carbon-chains and may contain a chiral centre in the latter case; suitable examples of such alkyl groups are named above for R' and R2.
The indices m and n in formula (2) signify 0 or 1 in each case with the condition that the sum of m plus n may not exceed one.
In many instances compounds of formula (1) or (2) are preferred in which R1 and R2 or R3 and R4 are identical or different C3~9-alkyl groups. It is often advantageous when R' or R3 are the n-pentyl-, nhexyl-, or n-heptyl-groups and R2 or R4 are the n-pentyl-group, especially in formula (2) when m as well as n are both zero.
Liquid crystal mixtures claimed by the invention contain at least one compound of formula (1) or (2) in each case, typically in proportions of 130% and preferably in proportions of 5-20%. The other components of such liquid crystal mixtures are those contained in known liquid crystal mixtures of overall negative dielectric anisotropy belonging to the state of the art. Also included are those additives often used in GHD's or HND's such as pleochroic dyes and similar additives.
The new biphenyl esters can be obtained simply via esterification or trans-esterification of the corresponding carboxylic acids (or carboxylic acid derivatives) of formula (3)
with the corresponding dicyanophenols of formula (4)
or the corresponding M-phenolates, e.g., alkali metal phenolates (M=alkali metal), which are obtainable from compounds of the formula (4).
R1, R2, X1, and X2 in the formulas (3) and (4) have the meaning given above, Z is the hydroxy group or a halogen atom, such as chlorine or bromine. However, when the compounds (1) are produced by trans-esterification Z may be a short-chained alkoxy-group, e.g., methoxy or ethoxy.
The reaction of the compounds (3) and (4) is carried out appropriately in a liquid medium, such as toluene or in another organic solvent which is inert to the compounds (3) and (4). When necessary the reaction is carried out in the presence of a material which can bond the side-product HZ or MZ (in the case of the phenolates of compound [4]) of the esterification.
When Z in formula (3) is a halogen then hydrogen halide is produced as HZ upon reaction with the phenol of formula (4). Suitable acid-binding substances are inorganic or organic bases, such as sodium carbonate or pyridine. Analogously when Z is an hydroxy group, then water is produced as HZ and then, for example, sulphuric acid or another dying agent is suitable as a water-binding agent. It is clear, that when water is produced during the esterification reaction or short-chained alcohols are produced during trans-esterification, then necessarily the reaction is carried out in a liquid medium, whose boiling point is higher than that of water or the short-chained alcohol respectively.
The esterification or trans-esterification is generally carried out at high temperature, e.g., between 80 C and the reflux-temperature of the reaction mixture. The compounds (3) and (4) are preferably used in approximately equal amounts.
Suitable carboxy-compounds of formula (3) are known or can be obtained from known compounds via standard reaction methods.
Dicyanophenols of the formula (4) or the corresponding alkali metal phenolates (M is, for example, sodium) can be prepared according to the reaction scheme below:
Cl Cl CgCl H3COX (1) Frledel-Cratts H3CO C-Ri R'C(0)CL Co11 C- H2 R1 ~~~~~~~~~~~~~~~~~~~ H3CO- t2) Reduction CN N (3) Cyanation H3cOOCH2R CN CN Ho4CH2R1 (4) Dernethylation The Friedel-Crafts reaction (1) can be carried out in the usual way, e.g., with anhydrous aluminium chloride in an inert solvent with the exclusion of moisture. The group R' of the acid chloride
R'C(O)CI is one methylene unit shorter than the desired alkyl group R2.
The reduction (2) can be carried out as usual with lithium-aluminium hydride.
The cyanation (3) can be carried out using copper (I) cyanide according to the method of Gray et.
al. in J. Chem. Soc., Perkin Trans. 2, 97 (1976).
The demethylation (4) can finally be accomplished using a known method, e.g., by breaking the ether bond with methyl iodide.
The compounds of formula (1) described by the invention exhibit generally very high negative values of the dielectric anisotropy, i.e., they possess values of DA in the range -10 to -15 at a reduced temperature or extrapolated to room temperature. This is the case so long as the lateral polarisation of the molecules (1) by the two nitrile functions is not compensated to any significant degree by the contributions to the dielectric anisotropy of the groups X' or x2 in the biphenyl part of the molecule, when they are not both hydrogen atoms.
The compounds of formula (1) possess relatively high values of the birefringence, typically approximately 0,2, which are characteristic of three-ring aromatic mono-esters. This has important consequences, especially in liquid crystal mixtures for HND's where it can be particularly advantageous.
The high birefringence of the compounds of formula (1) can be used to compensate for the low birefringence values, e.g., only 0.05, of other components of the liquid crystal mixtures. This can be done simply and without serious disadvantageous consequences.
In the following the preparation of the new compounds is illustrated by examples which in no way restrict the above mentioned claim; the liquid crystal transition temperatures describing the mesomorphic range are given in the usual way (C-N/I, N-I); C-I, represents the temperature in OC for the transition from the crystal to the isotropic liquid; C-N represents the temperature in OC of the transition from the crystal to the nematic phase; and N-I represents the temperature in OC of the transition from the nematic phase to the isotropic liquid.
Example 1
Preparation of (2,3-dicyano-4-pentylphenyl) 4'-pentylbiphenyl-4-carboxylate A solution of 4-pentylbiphenyl-4-carboxylic acid (1.0 g, 0.0037 mol) and thionyl chloride (25 cm3) was heated at an oil-bath temperature of 800C for approximately one hour in the usual way. The reacting solution was evaporated down under reduced pressure and sodium-dried toluene (20 cm3) was added and the resultant solution was evaporated down to dryness under reduced pressure.
The crude acid chloride thus obtained was used without further purification. The acid chloride was taken up in sodium-dried toluene (50 cm3) and a solution of 2.3-dicyano-4-pentylphenol (0.8 g, 0.0037 mol; mp 1420C) in freshly distilled, sieve-dried pyridine (10cm3) was added underthe exclusion of moisture. The resultant mixture was heated under reflux for one hour.
The cooled reaction mixture was added to dilute hydrochloric acid and extracted with chloroform (3 x50 cm3). The combined organic layers were washed with water (2x250 cm3) and dried over anhydrous magnesium sulphate. The chloroform was removed under reduced pressure and the raw product was purified using column-chromatography on silica-gel using toluene as eluent. After removal of the toluene the product was crystallised from ethanol until the liquid crystal transition temperatures were constant. The corresponding values for the desired product were C--N=990C; N-l=1 1 30C.
The 4'-substituted biphenyl-4-carboxylic acid can be obtained, for example, according to the method described by G. W. Gray and D. Coates in Mol. Cryst. Liq. Cryst., 37, 249 (1976). The 2,3-di cyano-4-pentylphenol can be obtained according to the reaction pathway described above.
By use of the coriesponding biphenyl carboxylic acids of the above mentioned formula (3) and the corresponding dicyanophenol of the above mentioned formula (4), the following compounds covered by the invention are obtainable (further examples of the invention are also described in Tables I and II):: (2,3-Dicyano-4-pentylphenyl) 4'-methylbiphenyl-4-ca rboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-ethylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-octylbiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-(2-methylbutyl)-biphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-methoxybiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-ethoxybiphenyl-4-carboxylate
(2,3-Dicyano-4-pe ntylphenyl) 4'-propyloxybiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-butyloxybiphenyl)-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-pentyloxybiphenyl)-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-heptyloxybiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-propylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-pentylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-heptylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-(2-methylbutyl)-biphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 4'-ethoxybiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-butyloxybiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-hexyloxybiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-propylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-pentylbiphenyl-4-carboxylate (2,3-Dicyano-4-heptylphenyl) 4'-.heptylbiphenyl-4-carboxylate (2,3-Dicyano-4-heptylphenyl) 4'-(2-methylbutyl)-biphenyl-4-carboxylate (2,3-Dicyano-4-heptyl phenyl) 4'-eth oxybi phenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-butyloxybiphenyl-4-ca rboxylate (2,3-Dicyano-4-heptylphenyl) 4'-hexyloxybiphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 2'4luoro-4'-propylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 2'-fluoro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 2'-fluoro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 2'-fluoro-4'-heptylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 2'-fluoro-4'-propylbiphenyl-4-carboxylate (2,3-Drcyano-4-pentylphenyl) 2'-fl uoro-4'-pentylbiphenyl-4-ca rboxylate
(2,3-Dicya no-4-pentylphenyl) 2'-fluoro-4'-heptylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 2'-fluoro-4'-propylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 2'-fluoro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 2'-fluoro-4'-heptylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 3'-fluoro-4'-propylbiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 3'-fluoro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 3'-fluoro-4'-heptylbiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 3'-fluoro-4'-propylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 3'-fluoro-4'-pentylbiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 3'-fluoro-4'-heptylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 3'-fluoro-4'-propylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 3'-fluoro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 3'-fluoro-4'-heptylbiphenyl-4-carboxylate
(2,3-Dicyano-4-propylphenyl) 4'-propyl-2-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-pentyl-2-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-heptyl-2-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-propyl-2-fl uorobiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-pentyl-2-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-heptyl-2-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-propyl-2-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-pentyl-2-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-heptyl-2-fl uorobiphenyl-4-ca rboxylate (2,3-Dicyano-4-propylphenyl) 4'-propyl-3-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-propylphenyl) 4'-pentyl-3-fluorobiphenyl-4-ca rboxylate (2,3-Dicyano-4-propylphenyl) 4'-heptyl-3-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-propyl-3-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-pentyl-3-fl uorobiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-heptyl-3-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-propyl-3-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-heptylphenyl) 4'-pentyl-3-fluorobiphenyl-4-carboxylate (2,3-Dicyano-4-heptylphenyl) 4'-heptyl-3-fluorobiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 2'-chloro-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 3'-chloro-4'-pentylbiphenyl-4-carboxylate (2,3-Dicyano-4-pentylphenyl) 4'-pentyl-2-chlorobiphenyl-4-carboxylate
(2,3-Dicyano-4-pe ntylphenyl) 4'-pentyl-3-chlorobiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 2'-bromo-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 3'-bromo-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-pentyl-2-bromobiphenyl-4-carboxylate (2 ,3-Dicyano-4-pentylphenyl) 4'-pentyl-3-bromobiphenyl-4-ca rboxylate
(2,3-Dicyano-4-pentylphenyl) 2'-cyano-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 3'-cyano-4'-pentylbiphenyl-4-carboxylate
(2,3-Dicyano-4-pentylphenyl) 4'-pentyl-2-cyanobiphenyl-4-carboxylate
(2,3-Dicya no-4-pentylphenyl) 4'-pentyl-3-cyanobiphenyl-4-ca rboxylate.
In the following Table I the liquid crystal transition temperatures for the compounds below are given (C-N/I represents the temperature C for the transition from the crystaliine state into the nematic or isotropic liquid state; N-I represents the temperature in C for the transition from the nematic phase into the isotropic liquid).
The enthalpies of fusion AH in kilojoules per mole (kJ mol-') for the above mentioned esters are also given.
Table I C-N/I N-I* AH R { C) (0C) (kJ . Mol-)
CH3 125 (122) C2H5 135 (98.5)
C3H7 109.5 (108) 31.8 QHs 108.5 (103) 35.1
C5H11 99 113 30.5
C6H13 93 109 31.8 C7H,s 98 113 31.4 CsHi7 94.5 109.5 33.5 CH3O 133.5 168
C2H50 151 174
C3H70 137 157 C4HgO 123 156 C5H110 129.5 151.5
C6H130 128.5 152 24.3
C7H150 125.5 149
*The values in () represents monotropic transitions.
In the following Table II similar values to those in Table I are given for the compounds of the formula shown below:
Table II C-Nfl N-I* AH R (0C) { C) (kJ.MoP1) CH3 118.5 (115)
C2H5 102 (95.5)
C3H7 95.5 103.5 C4H9 87.5 100 29.3
C5H1, 93 110 31.8
C6H13 83.5 108 11.7 C7H,s 86.5 112
C8H17 84 110.5 11.3 CH3O 126 158
C2H50 149.5 164.5
C3H70 133 150 C4HgO 124.5 1 53 C5H1,0 132 147
C6H130 131 148
C7H150 127.5 146.5
*The values in () represent monotropic transitions
Claims (10)
1. Novel substituted biphenyl esters with stable nematic phases and negative dielectric anisotropy for use in electro-optic displays, given by the formula (1)
R' is the hydrogen atom or an alkyl-, alkoxy-, or alkanoyloxy group, whose carbon chains contain 1-12 carbon atoms in normal or branched chains and which may contain a chiral centre in the latter case; R2 is an alkyl group with 1-12 carbon atoms arranged in normal or branched carbon chains and which may contain a chiral centre in the latter case;
X' and X2 are identical or different and may be hydrogen, fluorine, chlorine, bromine atoms or nitrile functions.
2. Compounds according to claim 1, in which only one of X1, X2 is not the hydrogen atom.
3. Compounds according to claim 2, in which either X' or X2 is the fluorine atom.
4. Compounds according to claim 1, described by the formula (2)
in which R3 and R4 are identical or different alkyl groups with 1-12 carbon atoms in normal or branched chains and which may contain a chiral centre in the latter case; n and m are 0 or 1 in each case, but the sum of n and m may not exceed 1.
5. Compounds according to claim 4, in which R3 and R4 are identical or different alkyl chains with 3-9 carbon atoms in each case.
6. Compounds according to claims 4 or 5, in which R3 is n-pentyl, or n-hexyl, or n-heptyl.
7. Compounds according to claim 6, in which R4 is n-pentyl and n and m are both 0.
8. Nematic liquid crystal mixtures with an overall negative dielectric an isotropy containing at least one nematic compound of high negative dielectric an isotropy, whereby the compound of high negative dielectric an isotropy is a compound of formula (1)
in which R1 is the hydrogen atom or an alkyl-, alkoxy-, or alkanoyloxy-group, whose carbon chains contain 1-1 2 carbon atoms and may be normal or branched and which may contain a chiral centre in the latter case; R2 is an alkyl chain with 1-1 2 carbon atoms and may be normal or branched and which may contain a chiral centre in the latter case; X' and X2 are identical or different and are hydrogen, fluorine, chlorine or bromine atoms or nitrile functions.
9. Mixtures according to claim 8, whereby the compound of high negative dielectric anisotropy corresponds to the formula (2)
in which R3 and R4 are identical or different alkyl groups with 1-12 carbon atoms and may be normal or branched and which may contain a chiral centre in the latter case; n and m are 0 or 1 in each case and the sum of m and n may not exceed 1.
10. Mixtures according to claims 8 or 9, whereby they are constituted from 1-30 mol% of at least one of the compounds of formula (1) or (2).
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH480582A CH651822A5 (en) | 1982-08-11 | 1982-08-11 | BIPHENYLESTER DERIVATIVES AND LIQUID CRYSTAL MIXTURES WITH THESE. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8321365D0 GB8321365D0 (en) | 1983-09-07 |
| GB2125043A true GB2125043A (en) | 1984-02-29 |
Family
ID=4282853
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08321365A Withdrawn GB2125043A (en) | 1982-08-11 | 1983-08-09 | Liquid crystal dicyanophenyl biphenylcarboxylic esters |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5953460A (en) |
| CH (1) | CH651822A5 (en) |
| DE (1) | DE3324686A1 (en) |
| GB (1) | GB2125043A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4939287A (en) * | 1985-09-30 | 1990-07-03 | Hoechst Aktiengesellschaft | Chiral esters of mesogenic carboxylic acids |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2035303A (en) * | 1978-09-20 | 1980-06-18 | Chisso Corp | 2,3-dicyano-hydroquinone derivatives |
| EP0019665A1 (en) * | 1979-05-28 | 1980-12-10 | MERCK PATENT GmbH | Liquid-crystal compositions |
| EP0023728A1 (en) * | 1979-07-18 | 1981-02-11 | MERCK PATENT GmbH | Anisotropic compounds with negative or positive direct anisotropy and limited optical anisotropy, and liquid crystal mixtures containing them |
| WO1982000654A1 (en) * | 1980-08-22 | 1982-03-04 | S Belyaev | New derivatives of phenic acid,method of obtaining them,liquid crystal material with negative dielectric anisotropy,method of obtaining that liquid crystal material,liquid crystal material with low-frequency inversion of sign of dielectric anisotropy and method of obtaining that liquid crystal material |
-
1982
- 1982-08-11 CH CH480582A patent/CH651822A5/en not_active IP Right Cessation
-
1983
- 1983-07-08 DE DE19833324686 patent/DE3324686A1/en not_active Withdrawn
- 1983-08-08 JP JP14393183A patent/JPS5953460A/en active Pending
- 1983-08-09 GB GB08321365A patent/GB2125043A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2035303A (en) * | 1978-09-20 | 1980-06-18 | Chisso Corp | 2,3-dicyano-hydroquinone derivatives |
| EP0019665A1 (en) * | 1979-05-28 | 1980-12-10 | MERCK PATENT GmbH | Liquid-crystal compositions |
| EP0023728A1 (en) * | 1979-07-18 | 1981-02-11 | MERCK PATENT GmbH | Anisotropic compounds with negative or positive direct anisotropy and limited optical anisotropy, and liquid crystal mixtures containing them |
| WO1982000654A1 (en) * | 1980-08-22 | 1982-03-04 | S Belyaev | New derivatives of phenic acid,method of obtaining them,liquid crystal material with negative dielectric anisotropy,method of obtaining that liquid crystal material,liquid crystal material with low-frequency inversion of sign of dielectric anisotropy and method of obtaining that liquid crystal material |
| GB2094311A (en) * | 1980-08-22 | 1982-09-15 | Ivaschenko Aleksandr Vasilevic | New derivatives of phenic acid method of obtaining them liquid crystal material with negative dielectric anisotropy method of obtaining that liquid crystal material liquid crystal material with low frequency in version of sign of dielectric anisotropy and method of obtaining that liquid crystal material |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4939287A (en) * | 1985-09-30 | 1990-07-03 | Hoechst Aktiengesellschaft | Chiral esters of mesogenic carboxylic acids |
| US5043095A (en) * | 1985-09-30 | 1991-08-27 | Hoechst Aktiengesellschaft | Chiral esters of mesogenic carboxylic acids in liquid crystal phases |
Also Published As
| Publication number | Publication date |
|---|---|
| CH651822A5 (en) | 1985-10-15 |
| GB8321365D0 (en) | 1983-09-07 |
| JPS5953460A (en) | 1984-03-28 |
| DE3324686A1 (en) | 1984-02-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732 | Registration of transactions, instruments or events in the register (sect. 32/1977) | ||
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |