Benzochromene derivatives, some of which are new, e.g. used in liquid crystal media, especially in vertically aligned nematic electrooptical displays

摘要

Benzochromene derivatives and liquid crystal media containing them are new. Benzochromene derivatives of formula (I) are new. [Image] Y : -CO-, -CS-, -CH 2-, -CF 2- or -CHF-; L 1and L 2H, F, Cl or CN, with the proviso that when Y = -CO-, then at least one of L 1and L 2is not H; rings A 1and A 2(a) trans-1,4-cyclohexylene optionally with 1 or 2 non-adjacent CH 2replaced by -O- and/or -S-, (b) 1,4-cyclohexenylene, (c) 1,4-phenylene optionally with 1 or 2 CH replaced by N or (d) 1,4-bicyclo-[2.2.2]-octylene, 1,3-bicyclo-[1.1.1]- pentylene, spiro-[3.3]-heptane-2,4-diyl, piperidine-1,4-diyl, naphthylene-2,6-diyl, decahydronaphthylene-2,6-diyl or 1,2,3,4-tetrahydronaphthylene-2,6-diyl; R 1and R 2H, halogen, CN, SCN, SF 6, CF 3, CHF 2, CH 2F, OCF 3, OCHF 2or 1- 15C alkyl mono-substituted by CN or CF 3or at least mono-substituted by halogen, this alkyl group optionally also having 1 or more CH 2replaced by -O-, -S-, - CH:CH-, -CF:CF-, -CF:CH-, -CH:CF-, 1,3-cyclobutylene, -CO-, -CO-O-, -O-CO- or - O-CO-O- such that the O and S atoms are not directly linked to each other; Z 1and Z 2-CH 2-CH 2-, -CF 2-CF 2-, -CF 2-CH 2-, -CH 2-CF 2-, -CH:CH-, -CF:CF- , -CF:CH-, -CH:CF-, -Ctriple boundC-, -COO-, -OCO-, -CH 2O-, -CF 2O- and/or -OCF 2- such that no 2 O atoms are linked to each other; n and m : 0, 1 or 2; and n + m : 0, 1 ,2 or 3 An independent claim is also included for liquid crystal media with a nematic phase and containing compounds (I) with the exception that compounds with both L 1and L 2= H when Y = -CO- can be used.