Patent ID: 7087272

Claim:
A fluorene compound of formula I R 1 —(—A 1 —Z 1 —) k1 —(—A 2 —Z 2 —) k2 —W—(—Z 3 —A 3 —) k3 —(—Z 4 —A 4 —) k4 —R 2 I in which W is the group, L 1 and L 2 , independently of one another, are H, F, Cl, —CH 2 F, —CHF 2 or —CF 3 , with the proviso that L 1 and L 2 are not both H, L 3 and L 4 , independently of one another, are H or F, wherein one of L 3 and L 4 is H and the other is F, R 1 and R 2 , independently of one another, are H, halogen, —CN, —NCS, —SF 5 or alkyl having from 1 to 18 carbon atoms, in which, in addition, one or two non-adjacent —CH 2 — groups may be replaced by —O—, —S—, —CO—, —O—CO—, —CO—O—, —E— and/or —C≡C—and/or in which, in addition, one or more H atoms may be replaced by halogen and/or —CN, E is CR 4 ═CR 5 or CHR 4 —CHR 5 , R 4 and R 5 are each, independently of one another, H, alkyl having 1–6 carbon atoms, F, Cl, CF 3 or CN, A 1 , A 2 , A 3 and A 4 are each, independently of one another, 1,4-phenylene, in which one or more CH groups may be replaced by N, 1,4-cyclohexylene, in which one or two non-adjacent CH 2 groups may be replaced by O and/or S, 1,4-cyclohexenylene, 1,4- bicyclo[2.2.2]octylene, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl or 1,2,3,4-tetrahydronaphthalene-2,6-diyl, where, in the meanings given for A 1 , A 2 , A 3 and A 4 , one or more H atoms may be substituted by halogen, —CN and/or alkyl having from 1 to 6 carbon atoms, in which one or more H atoms may be replaced by halogen or —CN, and/or in which one or more non-adjacent —CH 2 — groups may be replaced, independently of one another, by —CO—, —O—CO—, —CO—O—, —O—, —S—, —CH═CH— or —C≡C—, and Z 1 , Z 2 , Z 3 and Z 4 , independently of one another, are —O—CO—, —CO—O—, —CH 2 —O—, —CF 2 —O—, —O—CH 2 —, —O—CF 2 —, —C 2 H 4 —, —CH 2 —CF 2 —, —CF 2 —CH 2 —, —CF 2 —CF 2 —, —CH═CH—, —CF═CH—, —CH═CF—, —CF═CF—, —C≡C— or a single bond, k1, k2, k3 and k4, independently of one another, are 0, 1 or 2.