Patent ID: 7041345

Claim:
A chiral compound of the formula I wherein X 1 and X 2 form together a bivalent radical selected from —CH 2 —, —CHR 1 —, —CR 1 R 2 —, —SiR 1 R 2 — or 1,1-cycloalkyliden, X 3 and X 4 are H or have one of the meanings given for X 1 and X 2 , Y 1 , Y 2 , Y 3 and Y 4 are each independently as defined for R 1 , A or -M-R 3 , A is a cyclic group, M is a mesogenic group, R 1 and R 2 have independently from each other one of the meanings of R 3 or -M-R 3, and R 3 is: H, F, Cl, Br, CN, SCN, or SF 5, or a chiral or achiral alkyl group with 1 to 30 C atoms which is unsubstituted, or mono- or polysubstituted by F, Cl, Br or CN, one or more non-adjacent CH 2 groups optionally being replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH 3 )—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that oxygen atoms are not linked directly to one another, or a polymerizable group, wherein at least one of Y 1 , Y 2 , Y 3 and Y 4 is -M-R 3 , and wherein at least one group M in the compound is of formula II -A 1 -(Z-A 2 ) m - II wherein A 1 and A 2 are independently from one another 1,3- or 1,4-phenylene in which one or more CH groups are optionally replaced by N; 1,3- or 1,4-cyclohexylene in which one or two non-adjacent CH 2 groups are optionally replaced by O and/or S; 1,3-dioxolane-4,5-diyl; 1,4-cyclohexenylene; 1,4-bicyclo-(2,2,2)-octylene; piperidine-1,4-diyl; decahydronaphthalene-1,6- or -2,6- or -3,6-diyl; 1,2,3,4-tetrahydronaphthalene-1,6- or -2,6- or -3,6-diyl; or indane-2,5-diyl; all these groups being unsubstituted, or mono- or polysubstituted with halogen, cyano or nitro groups or alkyl, alkoxy, alkylcarbonyl or alkoxycarbonyl groups with 1 to 7 C atoms, wherein one or more H atoms are optionally substituted by F or Cl, Z is in each case independently —O—, —S—, —CO—, —COO—, —OCO—, —O—COO—, —CO—N(R 0 )—, —N(R 0 )—CO—, —SCH 2 —, —CH 2 S—, —CF 2 O—, —OCF 2 —, —CF 2 S—, —SCF 2 —, —CH 2 CH 2 —, —CF 2 CH 2 —, —CH 2 CF 2 —, —CF 2 CF 2 —, —CH═CH—, —CF═CH—, —CH═CF—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or a single bond, R 0 is H or alkyl with 1 to 4 C atoms, and m is in each case independently 1, 2, 3 or 4, provided that all of Y 1 , Y 2 , Y 3 and Y 4 are not simultaneously -M-R 3 wherein A 1 and A 2 are 1,4-phenylene, Z is a single bond, m is 1 and R 3 is H.