Bifunktionelle Vorprodukte zur Herstellung von Flüssigkristallen

摘要

The invention concerns bifunctional compounds of formula (I) in which (a) and (b) are naphthalene-2,6-diyl or (c); (d) is naphthalene-2,6-diyl or (e); U, X, Y, Z are -CH=, -CF= or -N=, with the provision that -CF= or -N= each occur at the most twice in each six-membered ring and that -CF= and -N= do not both occur together twice in a six-membered ring; Hal is Cl, Br or I (or H if X and/or Y are -CF=; R<3> is CH3 or OCH3; l is 0 or 1 and m and n are 0, 1, 2 or 3. Compounds of formula (I) are useful intermediates in the manufacture of liquid-crystal mixtures.