摘要:
Process for cross-coupling aromatic boron compounds with aromatic halogen compounds or perfluoroalkylsulfonates.In a process for preparing polycyclic aromatic compounds by cross-coupling aromatic boron compounds with aromatic halogen compounds or perfluoroalkylsulfonates under palladium catalysis in the presence of at least one water-soluble complex ligand, the reaction medium comprises an aqueous and an organic phase and the palladium is added in the form of a palladium compound soluble in the organic phase.Polycyclic aromatic compounds can thus be prepared economically and in very good yields and simultaneously very high purity, in particular without contamination by the complexing ligands.
摘要:
1,8,8-Trifluoro-5,6,7,8-tetrahydroisoquinoline derivatives, and their use in liquid-crystalline mixtures 1,8,8-Trifluoro-5,6,7,8-tetrahydroisoquinoline derivatives of the formula (I)R.sup.1 (--M.sup.1).sub.a (--A.sup.1 --M.sup.2).sub.b (--A.sup.2 --M.sup.3).sub.c --B(--M.sup.4 --A.sup.3).sub.d (--M.sup.5 --A.sup.4).sub.e (--M.sup.6).sub.f --R.sup.2 (I)in which the symbols and indices have the following meanings:the group B is ##STR1## R.sup.1 and R.sup.2 are, for example, alkyl radicals having 1 to 20 carbon atoms;M.sup.1, M.sup.2, M.sup.3, M.sup.4, M.sup.5 and M.sup.6 are, for example, --O--, --CO--O--, --O--CO-- or a single bond;A.sup.1, A.sup.2, A.sup.3 and A.sup.4 are, for example, 1,4-phenylene, pyrimidine-2,5-diyl or trans-1,4-cyclohexylene, anda, b, c, d, e and f are zero or one, with the proviso that the sum of b, c, d and e is 0, 1 or 2.The compounds of the formula (I) are colorless in the pure state and generally form liquid-crystalline mesophases in a temperature range which is favorably located for electro-optical use. They are stable chemically, thermally and to light.
摘要:
1-Fluoro-6,7-dihydro-5H-isoquinolin-8-one derivatives of the formula (I)R.sup.1 (--M.sup.1).sub.a (--A.sup.1 --M.sup.2).sub.b (--A.sup.2 --M.sup.3).sub.c --B(--M.sup.4 --A.sup.3).sub.d (--M.sup.5 --A.sup.4).sub.e (--M.sup.6).sub.f --R.sup.2 (I)where B, R.sup.1, R.sup.2, M.sup.1, M.sup.2, M.sup.3, M.sup.4, M.sup.5 M.sup.6, A.sup.1, A.sup.2, A.sup.3, and A.sup.4 are various defined substituents and a, b, c, d, e are zero or one, with the proviso that the sum of b, c, d, and e is 0, 1 or 2, are disclosed. These derivatives are used in liquid-crystalline mixtures.
摘要:
Bifunctional compounds of the formula (I), ##STR1## in which: ##STR2## are naphthalene-2,6-diyl or ##STR3## is naphthalene-2,6-diyl or ##STR4## U, X, Y and Z are --CH.dbd., --CF.dbd. and --N.dbd., with the proviso that --CF.dbd. and --N.dbd. may each only be represented at most twice per six-membered ring, and that --CF.dbd. and --N.dbd. may not at the same time be represented twice in a six-membered ring;Hal is Cl, Br or I; or H, if X and/or Y are --CF.dbd.R.sup.3 is CH.sub.3 or OCH.sub.3l is 0 or 1m and n are 0, 1, 2 or 3.The compounds of the formula I are useful intermediates for the preparation of liquid-crystalline mixtures.
摘要:
Novel oxiranylmethyl ethers can advantageously be employed in liquid-crystal mixtures since they have high spontaneous-polarization values and features in their molecular structure which make them miscible with other components of liquid-crystal systems.
摘要:
3-Chloropyridines, process for their preparation, and their use in liquid-crystal mixturesA 3-chloropyridine of the formula (I) ##STR1## in which the symbols have the following meaning: R.sup.1 and R.sup.2, independently of one another, are, for example, H or straight-chain or branched alkyl, A.sup.1, A.sup.2, A.sup.3 and A.sup.4 are identical or different and are, for example, 1,4-phenylene, pyrazine-2,5-diyl or trans-1,4-cyclohexylene, M.sup.1, M.sup.2, M.sup.3 and M.sup.4 are identical or different and are, for example, --O-- or --CO--O--, R.sup.3, R.sup.4, R.sup.6 and R.sup.7, independently of one another are, for example, H or straight-chain or branched alkyl, M.sup.5 is, for example, --O--CO-- or a single bond, k, l, m, n, o, p, q and r are zero or one, with the proviso that the sum k+m+p+r is less than 4 and greater than zero, can advantageously be employed as a component in ferroelectric liquid-crystal mixtures.
摘要翻译:3-氯吡啶,其制备方法及其在液晶混合物中的应用将式(I)的3-氯吡啶(I)(M3)o(A3)p(M4)q(A4)rR2在 这些符号具有以下含义:R 1和R 2彼此独立地为例如H或直链或支链烷基,A 1,A 2,A 3和A 4相同或不同,为例如1, 4-亚苯基,吡嗪-2,5-二基或反-1,4-亚环己基,M1,M2,M3和M4相同或不同,为例如-O-或-CO-O-,R3,R4 R 6和R 7彼此独立地是例如H或直链或支链烷基,M 5是例如-O-CO-或单键,k,l,m,n,o,p ,q和r为零或一个,条件是和k + m + p + r小于4且大于零,可有利地用作铁电液晶混合物中的组分。
摘要:
Azaaromatic compounds of the formula I ##STR1## in which R.sup.1 and R.sup.2 are, for example, alkyl radicals,M is, for example, --O--, --COO-- or --O--CO--O--,A is an aromatic or heteroaromatic ring,V, X, Y and Z are CH, CF or N,a,b,c,d,m and n are 0 or 1, where m+n is 0 or 1 and a+d is 0 or 1.The compounds of the formula I are suitable as components of liquid-crystal mixtures.
摘要:
Decomposition-sensitive complex ligands can be stabilized by derivatizing them with the aid of bulky secondary or tertiary carboxylic acids or sulfonic acids. These stabilized derivatives can be added to alignment layers and liquid-crystal mixtures and increase the contrast and brightness in the FLC display.
摘要:
Modified polysugar as an alignment layer for liquid-crystal displaysAn alignment layer for liquid-crystal displays (LCDs) containsa) at least one oligomer/polymer of a 6-membered cyclic sugar unit all or some of whose free OH groups may be derivatized and which carries equatorial substituents in the 2-, 3- and 6-positions on the ring, andb) at least one compound from the group consisting of macrocyclic compounds, cryptands, coronands, podands, mercapto compounds and ionophores.LCDs which contain an alignment layer according to the invention are particularly distinguished by good contrast and bright-transmission values and by good alignment of the liquid crystal.