| 摘要 |
Optically active 5-hydroxypyridin-2-yl derivs. of formula (I) are claimed; one of the gps. R1, R2 = 1-15C alk(en)yl or perfluoroalk(en)yl, opt. mono-substd. with CN, Hal or CF3 and opt. with CH2 or CF2 gp(s). replaced by S, O, 1,3-cyclobutylene, a gp. of formula (II), CO, COO, OCO, or OCOO, so that S and/or O atoms are not directly linked; the other gps. R1, R2 = chiral gps. of formula (III) (with asterisk = chiral C linked to 4 different gps; Q2, Q3 = O, COO, OCO, (CH2)n, (CH2)nO, O(CH2)n, (CH2)nCOO, OCO(CH2)n (with n = 1-8) or a single bond; R3 = H, or Me; R4 = 1-8C alkyl; Y = CN, Hal, CF3 or Me); Q1 = CH2 or CO; A1, A2 = (a) trans-1,4-cyclohexylene (Cyc) (opt. with 1 or 2 non-adjacent CH2 replaced by O and/or S), (b) 1,4-phenylene (Phe) (opt. with 1 or 2 CH replaced by N) or (c) 1,3-cyclobutylene, 1,3-bicyclo (1.1.1)-pentylene, 1,4-bicyclo(2.2.2)octylene, piperidine-1,4-diyl, naphthalene-2,6-diyl or corresp. decahydro- or 1,2,3,4-tetrahydro- naphthalene derivs. (gps (a) and (b) can also be substd. with CN or Hal); Z1, Z2 = CH2CH2 -CC-, CH2O, OCH2, COO, OCO, CH=N, N=CH, CH2S, SCH2, single bond or 3-6C alkylene (opt. with one CH2 replaced by O, COO, OCO, CHHal or CHCN); m = 0, 1 or 2; Q1 = CH2 if A1 = unsubstd. Phe, Z1 = single bond, R4 = H, Y = Me and Q3 = single bond. Z1 = single bond, A1 = Phe substd. with 0, 1 or 2 F atoms, m = 0 and R2 = a gp. of formula (III) (with R4 = H), or R1 = gp. (III) (with R4 = H), Q1 = CH2, Z1 = single bond, A1 = Phe substd. with 0, 1 or 2 F atoms, m = 0. USE/ADVANTAGE - (I) are useful as component liq. crystalline (LC) media esp. ferroelectric LC media; addn. of (I) enables the prodn. of chiral tilted, smectic LC phases with high chemical stability, a good ferroelectric phase range, wide Sc phase range, excellent low-temp. stability (without crystallising), and high spontaneous polarisation. the claims include ferroelectric LC media contg. at least 2 LC components, at least one of which is a cpd. (I). and electro-optical display contg. such media as dielectric.
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