Abstract: Disclosed is a tetracyclic compound of the formula I in which R1, R2 are each, independently of one another, an alkyl or alkenyl radical having up to 15 carbon atoms which is unsubstituted, monosubstituted by CN or CF3, or monosubstituted by halogen. One or more CH2 groups in these radicals may also, in each case independently of one another be replaced by —O—, —S—, —CO—, —CO—O—, —O—CO— or —O—CO—O— such that the O atoms are not linked directly to one another. Z is —OCF2—, —CF2O— or a single bond. L1, L2, L3, and L4 are each, independently of one another, H or F. m is 1 or 2. Similar compounds, as well as liquid-crystalline media having these compounds, are also disclosed.

Abstract: 2,3,4,5-tetrafluorobenzene derivatives can be obtained in a particularly advantageous manner by reacting the corresponding chlorobenzene or (chloro, fluoro)-benzene derivatives with a fluorinating agent in the presence of a solvent and a catalyst at elevated temperature, which comprises carrying out the reaction initially under temperature and pressure conditions such that the respective 2,3,4,5-tetrafluoro-benzene derivative continuously distills off through a column, and subsequently setting temperature and pressure conditions such that residual fractions of the 2,3,4,5-tetrafluorobenzene derivative distill off with the corresponding 2,3,4-trifluoro-5-chloro compound.

Abstract: The invention relates to a fluoro-substituted alkenyl compound represented by formula (1) wherein Y1, Y2, Y3 and Y4 are each independently H or F, provided that at least one of Y1 and Y2 is F; Q1 is a single bond or an alkylene group of 1-20 carbon atoms, at least one —CH2— being optionally substituted by —O—, provided that two or more —O— are not adjacent to each other; Q2 is a single bond or —C≡C—; Rings A1, A2 and A3 are each independently a cyclohexane ring, a dioxane ring, a cyclohexene ring, a pyrimidine ring, a pyridine ring, or a benzene ring, or a benzene ring having at least one hydrogen atom substituted by F; Z1, Z2 and Z3 are each independently a single bond, —CH2CH2—, —CH2O—, —OCH2—, —COO—, —OCO—, —CH═CH—, —C≡C—, —CF2O—, or —OCF2; and m and n are each independently 0 or 1; provided that Y3 is F when Ring A3 is a cy

Abstract: The present invention provides a liquid crystalline compound having a difluoropropyleneoxy group as a bonding group, which is represented by Formula (1): wherein R1 and R2 each independently represent hydrogen, halogen, a cyano group or an alkyl group having 1 to 20 carbon atoms; rings A1 to A5 each independently represent a 1,4-cyclohexylene group, a 1,4-cyclohexenylene group or a 1,4-phenylene group; Z1 to Z4 each independently represent a single bond, —CH2CH2—, —CH2O—, —OCH2—, —COO—, —OCO—, —CH═CH—, —C≡C—, —CF2O— or —OCF2—; Y1, Y2, Y3 and Y4 each independently represent hydrogen or fluorine; and k, l, m and n each independently represent 0 or 1. This liquid crystalline compound has a large absolute value (|&Dgr;&egr;|) of a dielectric anisotropy and shows a relatively small refractive anisotropy.

Abstract: The invention relates to a process for producing a brominated trifluoromethylbenzene represented by the general formula (1). This process includes brominating in a liquid or gas phase a trifluoromethylbenzene, represented by the general formula (2), by bromine in the presence of a catalyst under a condition that the bromine is coexistent with chlorine, where n is an integer of 1-2, and m is an integer of 1-3 where n is an integer of 1-2. The catalyst is preferably iron chloride in the case of the bromination in a liquid phase. It is preferably activated carbon carrying thereon iron chloride in the case of the bromination in a gas phase. The trifluoromethylbenzene is turned to the brominated trifluoromethylbenzene with high reactivity and high yield.

Abstract: The present invention provides a liquid crystalline compound having a difluoropropyleneoxy group as a bonding group, which is represented by Formula (1): 1

Abstract: Olefins containing aromatic substituents are synthesized without the addition of phosphonium salts or phosphanes with the aid of a PdII compound as a catalyst in the presence of nitrogen-containing additives such as N,N-dimethylglycine and a base.

Abstract: Processes for the preparation of parylene dimers, and more particularly to processes for the preparation of derivatives of octafluoro-[2,2]paracylophane, otherwise known as AF4.

Abstract: A process is provided which allows a 1,4-bis(difluoroalkyl)benzene derivative to be produced inexpensively by a simple procedure without requiring any special facility. This process comprises causing a compound (A) of the following formula (1): wherein X1, X2, X3, and X4 independently stand for an oxygen or sulfur atom, Y1 and Y2 independently stand for a group of the formula: —CnH2n—, in which n is 2 or 3, k is an integer in the range of 0 to 4, G stands for a halogen group, an alkyl group, a perfluoroalkyl group, or an alkoxy group, and m is an integer in the range of 0 to 4, to react with a fluorine-containing species, the molar ratio of the fluorine-containing species to compound (A) being in the range of 20-40. The process is carried out in the presence of a bromine-containing compound, which is in an amount of 2 to 3 equivalences to the amount of compound (A), in an organic solvent at −80° C. to 30° C.

Abstract: Novel phenylcyclohexanes of the formula I 1

Abstract: Liquid crystalline compounds superior in having an eminent dielectric anisotropy, being stable against environment and having improved miscibility with other liquid crystalline compounds, as well as a liquid crystal composition with driving-ability at a low voltage and responsibility at a high-speed comprising the compounds as a constituting component, and a liquid crystal display element comprising the composition are provided, said compounds are fluoroalkoxybenzene derivatives expressed by the general formula (1) wherein A1, A2 and A3 each independently denote trans-1,4-cyclohexylene,1,4-phenylene or so; B, B2 and B3 each independently denote a single bond, 1,2-ethylene or so; R denotes an alkyl group having 1 to 15 carbon atoms optionally substitutable with a halogen atom(s); Rf denotes a fluoroalkyl group having 1 to 3 carbon; k, m, and n each independently denote 0 or 1; with the proviso that when k=0 is a case, then one of B1, B2 and B3 is a methyleneoxy bond or so, and that whe

Abstract: The invention concerns a process for the reaction of a perfluoroalkyl iodide of the formula CF3(CF2)h—I, where h is an integer from 4 to 18, with a compound having a terminal olefinic group, which comprises conducting said reaction in an aqueous medium containing 5 to 40% by weight of a water-soluble solvent and in the presence of from 0.02 to 0.5 equivalents of dithionite ion, based on the perfluoroalkyl iodide, at a temperature of from 0 to 40° C. and at a pH greater than 7.0.

Abstract: Provided are a liquid crystalline compound having a wide liquid crystal phase temperature range, low viscosity, a large elastic constant ratio K33/K11 and excellent solubility at low temperature, a liquid crystal composition using the same and a liquid crystal display.

Abstract: The subject-matter of the present invention is a process of use in perfluoroalkylation and a reactant for making use of this process. This process is defined in that it comprises a stage in which a material of formula RfH and a base (or a species capable of generating a base) are brought into contact, in a polar and anhydrous medium, with a substrate carrying at least one electrophilic functional group. Application to organic synthesis.

Abstract: A synthesis is provided for &agr;,&bgr;-difluoro-&bgr;-halo-ethenyl aromatic compounds such as &agr;,&bgr;,&bgr;-trifluorostyrenes by a process of reacting CFX2CFXI, wherein each X is independently F or Cl, provided that at least one X is Cl and at least one X is F, with an aromatic compound Ar to form (CFX2CFX)n—Ar, wherein n is 1, 2 or 3, and subsequently dechlorohalogenating this product to form (CFX═CF)n—Ar. Novel synthetic intermediate compounds are provided.

Abstract: Provided are liquid crystalline compounds having excellent physical properties and being excellent in miscibility with other liquid crystal materials; liquid crystal compositions comprising the crystalline compound; and liquid crystal display device fabricated by using the liquid crystal composition; the liquid crystalline compounds being specific chlorobenzene derivatives expressed by the general formula (1) Ra—A1—Z1—A2&Parenopenst;Z2—A3&Parenclosest;m&Parenopenst;Z3—A4&Parenclosest;nRb  (1) wherein Ra, Rb, A1 to A4, Z1 to Z3, m, and n are herein defined.

Abstract: A process for producing an octafluoro[2,2]paracyclophane includes the steps of (a) reacting 1,4-bis(trifluoromethyl)benzene with a halogenated silane represented by the general formula (1), in the presence of a low valence metal, thereby obtaining a novel compound (precursor) represented by the general formula (2); and (b) conducting in the presence of a fluoride ion a dimerization of the compound into the octafluoro[2,2]paracyclophane,

Abstract: Fluorine-containing, chiral liquid crystal compounds comprise (a) a chiral fluorochemical terminal portion comprising (i) at least one chiral center, which can optionally be heteroatom-substituted; (ii) a terminal fluoroalkyl, fluoroether, perfluoroalkyl, or perfluoroether group; and (iii) an alkylene or fluoroalkylene group optionally containing at least one catenary ether oxygen atom; (b) a chiral or achiral terminal portion consisting of a hydrocarbon or hydrocarbon ether group, and, when chiral, comprising at least one chiral center, which can optionally be heteroatom-substituted; and (c) a central core connecting the terminal portions; the alkylene or fluoroalkylene group of the chiral fluorochemical terminal portion having at least 3 in-chain atoms and being located between the chiral center of the chiral fluorochemical terminal portion and the central core. The compounds have smectic mesophases or latent smectic mesophases and are useful, for example, in liquid crystal display devices.

Abstract: A process for catalytic addition of haloalkanes to alkenes involving the step of reacting the haloalkane with the alkene in the presence of a catalyst. The catalyst is an organophosphite compound represented by the following formula: P(ORa)(ORb)(ORc), where Ra, Rb, and Rc are each an alkyl group or an aralkyl group.

Abstract: Provided are liquid crystalline compounds which are excellent in the miscibility with existing liquid crystalline compounds even at low temperatures and are electrically and chemically stable while having a high voltage holding ratio and a high &Dgr;∈; liquid crystal compositions comprising the compound; and liquid crystal display devices fabricated by using the composition; the liquid crystalline compounds are expressed by the general formula (1)

Abstract: Diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating agents are disclosed.

Abstract: A method of producing a difluorobenzyl ether derivative (6) in which a benzene derivative (1) is reacted with a base to form carbanion which is in turn reacted with a difluoromethane derivative (2) to give a benzene derivative (3) which is further reacted with a phenol derivative (5) in the presence of a base.

Abstract: A fluorination method of oxygen and halogen sites with diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating reagents is disclosed.

Abstract: Liquid crystalline compounds are provided which have an extremely high voltage holding ratio, altered only slightly by change of temperature, and which have a low threshold voltage and a high &Dgr;n. Also provided are liquid crystal compositions containing the liquid crystalline compound; and liquid crystal display devices containing the liquid crystal composition. The liquid crystalline compound is expressed by the general formula (1) wherein R, Y1 to Y16, X and Z1 to Z3 are defined in claim 1.

Abstract: Dichloro-tetrafluoro-[2,2]-paracyclophane (formula I), which is a novel compound useful as a material for forming a coating film by chemical vapor deposition, and a process for manufacturing thereof and poly-&agr;&agr;-difluoro-chloro-para-xylylene film prepared therefrom are disclosed. Dichloro-tetrafluoro-[2,2]-paracyclophane is manufactured by chlorinating tetrafluoro-[2,2]-paracyclophane. The film to be formed by chemical vapor deposition of dichloro-tetrafluoro-[2,2]-paracyclophane has remarkably improved thermostability, as compared with the conventional products and is expected to be applied in various fields.

Abstract: The invention is to provide liquid crystalline compounds which have a low viscosity, high negative dielectric anisotropy, high resistivity, and high voltage holding ratio, and are stable against heat and ultraviolet light; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices using the liquid crystal composition therein; the liquid crystalline compound is expressed by the general formula (1) wherein R1 and Y1 represent an alkyl group having 1 to 20 carbon atoms; X1, X2, and X3 independently represent single bond, 1,2-ethylene group, vinylene group, —COO—, —CF2O—, or —OCF2—; ring A1, ring A2, ring A3, and ring A4 independently represent trans-1,4-cyclohexylene, or 1,4-phenylene hydrogen atom on the ring may be replaced by fluorine atom or chlorine atom provided that at least one of ring A2, ring A3, and ring A4 represents 2,3-difluoro-1,4-phenylene; m and n are 0 or 1, and each elem

Abstract: The present invention provides liquid crystalline compounds having compatibility with the other liquid crystal materials and excellent stability, and having low viscosity and high transition temperature of the isotropic phase, liquid crystal compositions containing at least one kind of the liquid crystalline compounds, and liquid crystal display devices constituted by using the liquid crystal compositions. The liquid crystalline compounds are represented by the following formula: R—A1—Z1—A2—Z2—A3—Z3—A4—(CH2)m.

Abstract: A process is provided for increasing the fluorine content of benzene or pyridine rings which are optionally substituted with from 1 to 3 inert substituents. The process involves (a) contacting the ring with a metal fluoride composition comprising cupric fluoride (CuF.sub.2) at a temperature above 250.degree. C. sufficient to transfer F from cupric fluoride to the optionally substituted ring, thereby chemically reducing the metal fluoride composition; (b) oxidizing the reduced metal fluoride composition from (a) in the presence of HF to regenerate a metal fluoride composition comprising cupric fluoride; and (c) employing regenerated metal fluoride composition of (b) in (a).

Abstract: A liquid-crystalline medium based on a mixture of polar compounds of positive dielectric anisotropy, characterized in that it contains one or more compounds of the general formula I ##STR1## in which R, Y, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, L.sup.1 and m are as defined herein.

Abstract: A liquid crystalline compound represented by the general formula (1) ##STR1## wherein R.sub.1 represents an alkyl or alkoxy group having 1 to 10 carbon atoms, a cyano group, a halogen atom, or an alkyl or alkoxy halide group having 1 to 4 carbon atoms; R.sub.2 represents an alkyl group having 1 to 10 carbon atoms; rings A.sub.1, A.sub.2, A.sub.3, and A.sub.4 each independently represent a 1,4-phenylene or 1,4-cyclohexylene group; Z.sub.1, Z.sub.2, and Z.sub.3 each independently represent a covalint bond, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C-- or --COO--; 1 and m are 0 pr 1; and n is 0 to 10.

Abstract: This invention provides LC compositions useful as birefringent materials in electrooptic devices which exhibit zero or low negatively sloped birefringence dispersion (e.g., exhibiting positive birefringence dispersion significantly lower than that of currently available LC compositions) or more preferably positively sloped birefringence dispersion in which birefringence of the material increases with wavelength. The invention provides compounds useful as components of LC compositions which exhibit negative birefringence where n.sub.o is higher than n.sub.e. The compounds of this invention are dimers of LC-like compounds in which the monomers are linked to each other through a high birefringence moiety (dimerization linker). The LC monomers consist of an LC core and one or two tail groups. Preferred monomers for this invention have low birefringence in comparison to the birefrigence of the monomer linking moiety.

Abstract: Liquid crystalline compounds which have excellent compatibility with other liquid crystal materials, especially at low temperatures, high voltage holding ratio, low threshold voltage, their small temperature dependency, high .DELTA.n, and broad liquid phase temperature range, the compounds being represented by formula (1)Ra--A.sub.1 --Z.sub.1 --A.sub.2 --Z.sub.2 --(--A.sub.3 --Z.sub.3 --).sub.m --A.sub.0 --Rf (1)(wherein m is 0 or 1; A.sub.0, A.sub.1, A.sub.2 and A.sub.3 represent a six-membered ring, ring A.sub.0 is 1,4-phenylene which may be substituted with 1 to 3 of F and/or Cl, rings A.sub.1, A.sub.2 and A.sub.3, independently of one another, are selected from trans-1,4-cyclohexylene, 1,4-phenylene which may be substituted with one or more halogen atoms, cyclohexene-1,4-diyl or 1,3-dioxane-2,5-diyl; Z.sub.1, Z.sub.2 and Z.sub.3 represent a bridge between the rings and independently of one another, are selected from --(CH.sub.2).sub.2 --, --(CH.sub.2).sub.4 --, --CH.sub.2 O--, --OCH.sub.

Abstract: A fluorination method of oxygen and halogen sites with diaryl-, dialkoxyalkyl-, alkylalkoxyalkyl-, arylalkoxyalkyl- and cyclic aminosulfur trifluorides fluorinating reagents is disclosed.

Abstract: The invention relates to fluorocyclohexane derivatives of the formula I ##STR1## in which R.sup.1, Z.sup.1, Z.sup.2, L.sup.1, L.sup.2, L.sup.3 and X are as defined as below:X is alkyl or alkoxy having 1 to 10 carbon atoms which is unsubstituted or substituted by halogen, alkenyl or alkenyloxy having 2 to 10 carbon atoms which is unsubstituted or substituted by --CN, --CF.sub.3 or --F, or is --CN, --F, --OCHF.sub.2, --OCF.sub.3, --OCHFCF.sub.3 or --OCF.sub.2 CF.sub.3,L.sup.1, L.sup.2 and L.sup.3 are each, independently of one another, H or F,R.sup.1 is H, an alkyl or alkenyl radical having 1-12 carbon atoms which is unsubstituted, monosubstituted by CN or CF.sub.3 or substituted by halogen, where one or more non-adjacent CH.sub.2 groups in these radicals may also, in each case independently of one another, be replaced by --O--, --S--, --CO--, --.diamond.--, --CO--O--, --O--CO-- or --O--CO--O--,Z.sup.1 and Z.sup.2 are each, independently of one another, --CO--O--, --O--CO--, --CH.sub.2 O--, --O--, --O--CH.sub.

Abstract: The present invention provides a liquid-crystalline compound which has a reduced viscosity, a wide liquid crystal temperature range (high clearing point), a high chemical stability (extremely high specific resistance, high voltage holding ratio) and a high solubility with other liquid-crystalline compound(s) and preferably has a proper refractive index anisotropy. The present invention also provides a liquid crystal composition having excellent properties. The liquid-crystalline compound is represented by the following general formula (1): wherein R and R' each independently represents a C.sub.1-20 alkyl or halogenated alkyl group or a group obtained by replacing one or more --CH.sub.2 -- groups in the alkyl group by any of --O--, --S--, --CH.dbd.CH-- or --C.tbd.C--, provided that two or more --CH.sub.2 -- groups are not consecutively replaced by either --O-- or --S--; and Z.sub.1 and Z.sub.2 each independently represents a covalent bond or 1,2-ethylene group, provided that when both Z.sub.1 and Z.sub.

Abstract: Liquid crystalline compounds are disclosed which compounds are expressed by general formula (1) ##STR1## wherein R.sub.1 represents an alkyl group having 1 to 10 carbon atoms, ring A represents 1,4-phenylene or 1,4-cyclohexylene, each of X.sub.1, X.sub.2, X.sub.3, and X.sub.4 independently represents hydrogen atom or fluorine atom, Y.sub.1 represents CF.sub.3 or OCF.sub.3, and each of m, n, and p is independently an integer of 1 or 0. The liquid crystalline compounds have a wide temperature. The liquid crystalline compounds have a wide temperature range of nematic phase, low viscosity, large positive .DELTA..epsilon., high chemical stability, high miscibility with other liquid crystalline compounds at low temperatures, small temperature dependency of viscosity and .DELTA..epsilon., extremely high specific resistance (high voltage holding ratio), and good UV stability, and are preferably used for TFT.

Abstract: The present invention provides a method of preparing ortho-difluorobenzene derivatives, which comprises (a) providing a mixture of cyclohexenes by reacting chlorotrifluoroethylene (CTFE) and 1.3-diene in a flow reactor and distilling the resultant, and (b) dehydrohalogenating the mixture of cyclohexenes with a phase transition catalyst in :he presence of alkali metal hydroxide at temperature range of 40 to 150.degree. C. without using any organic solvent. The distillate having low boiling point, which is obtained during distillation of the resultant, is recycled into the flow reactor. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoic acid, which comprises (a) providing a mixture of 4-chloro-1-methyl-4,5,5-trifluorocyclohexene and 5-chloro-1-methyl-4,4,5-trifluorocyclohexene by reacting chlorotrifluoroethylene (CTFE) and isoprene and distilling the resultant.

Abstract: A compound expressed by the general formula (1): whereinR.sup.1 denotes an alkyl group having 1 to 20 carbon atoms in which one or more methylene groups in said group may be replaced by oxygen atoms or --CH.dbd.CH-- and one or more hydrogen atoms in said group may be replaced by fluorine or chlorine atoms, with the proviso that two or more methylene groups may not be continuously replaced by oxygen atoms;Y.sup.1 denotes a halogen atom, CN, CF.sub.3, CHF.sub.2 or an alkoxy group having 1 to 5 carbon atoms, in which at least one hydrogen atom is replaced by a fluorine atom and one or more hydrogen atoms may be further replaced by chlorine atoms;Z.sup.1, Z.sup.2 and Z.sup.3 each independently denote a covalent bond, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH-- or CF.sub.2 O--, with the proviso that at least one of Z.sup.1, Z.sup.2, and Z.sup.3 is --CF.sub.2 O--;rings A.sup.1, A.sup.2 and A.sup.

Abstract: Fluorine-containing, chiral liquid crystal compounds comprise (a) a chiral fluorochemical terminal portion containing at least one methylene group and optionally containing at least one catenary ether oxygen atom; (b) a saturated, chiral or achiral, hydrocarbon terminal portion; and (c) a central core connecting the terminal portions. The compounds have smectic mesophases or latent smectic mesophases and are useful, for example, in liquid crystal display devices.

Abstract: An optically active compound which itself generally exhibits no antiferroelectric liquid crystal phase, but which can be added to an antiferroelectric liquid crystal or composition thereof having a high threshold voltage to reduce the threshold voltage of the resulting composition. Also disclosed is an antiferroelectric liquid crystal composition containing the optically active compound, a process for reducing the threshold voltage of an antiferroelectric liquid crystal composition, a process for producing the optically active compound, and a process for producing an optically active carboxylic acid as an intermediate.

Abstract: A process for controlling the cone tilt angle of a tilted smectic liquid crystal composition comprises the step of combining (a) at least one liquid crystal composition comprising at least one smectic or latent smectic liquid crystal compound comprising (i) an aliphatic fluorocarbon terminal portion comprising a terminal fluoroalkyl or fluoroether group and an alkylene group having at least two carbon atoms and containing at least one catenary ether oxygen atom, (ii) an aliphatic hydrocarbon terminal portion, and (iii) a central core connecting the terminal portions; and (b) at least one liquid crystal composition comprising at least one smectic or latent smectic liquid crystal compound; with the provisos that at least one of the compositions (a) and (b) comprises at least one chiral liquid crystal compound and that the combining of compositions (a) and (b) provides an optically active, tilted chiral smectic liquid crystal composition.

Abstract: Novel phenylcyclohexanes of the formula I ##STR1## in which n is 0 to 7, Q.sup.1 and Q.sup.2 are H, or one of these radicals is alternatively CH.sub.3, r is 0, 1, 2, 3, 4 or 5, A is trans-1,4-cyclohexylene, 1,4-phenylene, 3-fluoro-1,4-phenylene or a single bond, X is F, Cl, --CF.sub.3, --CN, --OCF.sub.3 or --OCHF.sub.2, and Y and Z are each, independently of one another, H or F, with the proviso that, in the case where A is a single bond, Q.sup.1 =Q.sup.2 =H and simultaneously X=CN, Y and/or Z are F.

Abstract: Provided is a naphthalene compound represented by the following Formula (1): ##STR1## wherein R.sub.1 and R.sub.2 each represent a linear or branched alkyl group having 1 to 20 carbon atoms, an alkoxyalkyl group having 2 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms which may be substituted with halogen atoms and have no asymmetric carbon atoms; A represents any of the groups represented by the following formulas: ##STR2## (wherein X.sub.1, X.sub.2, X.sub.3 and X.sub.4 each represent a hydrogen atom or a halogen atom); and z represents 0 or 1. The addition of this naphthalene compound to a liquid crystal composition makes it possible to improve various characteristics such as the high speed response property of the liquid crystal composition and the temperature dependency of the response time. The above naphthalene compound is useful as a liquid crystal material for liquid crystal compositions, particularly ferroelectric liquid crystal compositions.

Abstract: A process for controlling the cone tilt angle of a tilted smectic liquid crystal composition comprises the step of combining (a) at least one liquid crystal composition comprising at least one smectic or latent smectic liquid crystal compound comprising (i) an aliphatic fluorocarbon terminal portion comprising a terminal fluoroalkyl or fluoroether group and an alkylene group having at least two carbon atoms and containing at least one catenary ether oxygen atom, (ii) an aliphatic hydrocarbon terminal portion, and (iii) a central core connecting the terminal portions, wherein the alkylene group of the aliphatic fluorocarbon terminal portion is directly linked to the central core by a moiety selected from the group consisting of a covalent bond, --CH.dbd.CH--, and --C.tbd.

Abstract: A process for the preparation of octafluoro-?2,2!paracyclophane includes contacting a reactant selected from the group consisting of 1,4-bis(bromodifluoromethyl)benzene (dibromide), 1,4-bis(chlorodifluoromethyl)benzene (dichloride), and 1,4-bis(iododifluoromethyl)benzene (diiodide) with trimethylsilyltributyltin (TMSTBT) (a reducing agent) and fluoride ions in a refluxing solution of hexamethylphosphoramide (HMPA) or dimethylsulfoxide (DMSO) in tetrahydrofuran (THF) at conditions effective to promote a reaction product comprising octafluoro-?2,2!paracyclophane.

Abstract: A novel 3-substituted .alpha.,.beta.-dibromoethylbenzene of formula (I): ##STR1## wherein X represents a halogen atom or a trihalomethyl group, which is useful as an intermediate for pharmaceuticals or agricultural chemicals, is prepared by a simple and high yield process which comprises reacting a 3-substituted .alpha.-bromoethylbenzene represented by formula (II): ##STR2## wherein X is as defined above, or a 3-substituted ethylbenzene represented by formula (III): ##STR3## wherein X is as defined above, with bromine in the presence of a quaternary ammonium salt.

Abstract: Methods of making parylene AF4 using novel that result in reduced cost. Low dilution technology may used to provide parylene AF4 in substantially improved yields. The relative amount of transition metal catalyst can be decreased. The amount of undesired byproduct is also reduced.

Abstract: Liquid-crystalline compounds of the formula I ##STR1## R is H, an alkyl or alkylene radical, Z.sup.1 and Z are each, independently of one another, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--,--C.tbd.C-- or a single bond, and one of the radicals Z.sup.1 and Z is alternatively --(CH.sub.2).sub.4 -- or --CH.dbd.CH--CH.sub.2 CH.sub.2 --,A is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--,A.sup.1 is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--, or is 1,4-phenylene which is unsubstituted or monosubstituted or disubstituted by fluorine and/or Cl atoms and in which, in addition, one or two CH groups may be replaced by N,W is --O--,Q is a single bond,m, o, s, r and t are as defined below,Y is F, Cl, OCF.sub.3, CHF.sub.2, OCHF.sub.2 or OCHF, and can be CF.sub.3,are suitable as components for liquid-crystalline media.

Abstract: Disclosed are derivatives of fluoroalkylethynyl- and difluoroalkylethynylbenzenes of the formula (I) herein. These compounds exhibit useful properties as liquid crystal compounds and are useful in nematic liquid crystal mixtures.

Abstract: The present invention relates to processes for the preparation of bromine-containing aromatic compounds, to novel bromine-containing compounds and to their use as intermediates in the synthesis of active substances. Processes according to the invention for the preparation of known and novel bromine-containing compounds are characterized by specific conditions.