Alkenyl-cyclohexane(s) for liquid crystal mixt. for super-twist LCD with high contrast and short switching time

摘要

Alkenyl-cyclohexane cpds. (IA-J) of formula R<1>-(A*)-(CH=CH)r-Cyc-CH=CH-(Cyc)s-R<2> (A), having substits. as follows, are new. (IA) : A* = Cyc; p, s = 1; r = 0; (IB) : A* = Cyc; p, r, s = 1; R<2> = alkyl; (IC) : p, r = 0; s = 1; R<1> = R<b>-CH=CH-(CH2)n-; (ID) : p, r = 0; s = 1 or 2; R<1> = Rb-CH=CH-(CH2)n-; R<2> = (CH2)o-CH=CH-Rb; (IE) : p, r = 0; s = 2; R<1> = Rb-CH=CH-(CH2)n-; (IF) : p, s = 1; r = 0; R<1> = Rb-CH=CH-(CH2)n; (IG) : p, r = 0; s = 1; R<1> = Rb-CH=CH-(CH2)n-; R<2> = Phe'-R<1>; (IH) : p, r = 0; s = 1 or 2; R<1> = Rb-CH=CH-(CH2)n-; R<2> = -(CH2)o-CH=CH-Rb'; (IJ) : p, s = 1; r = 0; Cyc = trans-1,4-cyclohexylene; Phe' = 1,4-phenylene (Phe), 3-fluoro-1,4-phenylene (Phe-F) or 3,5-difluoro-1,4-phenylene (Phe-2F) (end gp. in 4-position); in general, when not specified: A* = Cyc, Phe' or 2-fluoro-1,4-phenylene; R<1> = 1-10C alk(en)yl or alkoxy, opt. mono-substd. by CN or CF3 or at least mono-substd. by halogen, in which 1 or more CH2 gps. may be replaced by -O-; R<2> = (CH2)n-CH=CH-Ra, (CH2)n-CH=CH2 and, if r = 1, also Ra; Ra = 1-6C linear alkyl; Rb,Rb' = H or 1-6C alkyl; n, o = 0-6; r = 0, 1 or 2; s = 1 or 2. Also claimed are (i) a supertwist LCD contg. a nematic liquid crystal (LC) mixt. comprising LC components A, B and opt. D and an optically active component C, in which component B contains cpd(s). (I) of formula (A) with the general range of substits.; (ii) the LC mixt. per se; and (iii) new intermediates (II) of formula (I; p, r = 0; s = 1; R<1> = 1-6C alkyl-OOC-; R<2> = Rb).