| abstract |
The present invention relates to a process for the preparation of a compound of the general formula n nR-(A 1 -Z-) m B—CF 2 O-A 2 -(A 3 ) n -R′ (I) nin which n R is alkyl, in which one or more CH 2 groups may be replaced, independently of one another, by O, CF 2 , CH═CH, CH═CF or CF═CF, with the proviso that peroxide structures O—O and formaldehyde acetals O—CH 2 —O are excluded, A 1 is, independently of one another, 1,4-cyclohexylene, 2,5-1,3-dioxanylene, 1,3-cyclobutylene or n n A 2 and A 3 are 1,4-phenylene, in which, independently of one another, from one to four hydrogens may be replaced by fluorine or one or two CH groups may be replaced by N, Z is a single bond, —CH 2 —CH 2 —, —CF 2 —CF 2 —, —CH═CH—, —CF═CF—, —CH═CF— or —CF═CH—, B is 2,6-disubstituted naphthalene, 2,6-disubstituted 5,6,7,8-tetrahydronaphthalene or 2,6-disubstituted trans-decalin, R′ is R, F, OCF 3 , OCF 2 H, CF 3 , CI, SF 5 , CN or NCS, and m and n are, independently of one another, 0 or 1, comprising the following steps: a) conversion of a compound of the general formula n nR-(A 1 -Z-) m BX (II), nin which X is halogen or ═O and the other symbols are as defined in relation to the formula (I), into a carboxylic acid derivative with elimination of the group X and introduction of a C1 unit; b) reaction of the carboxylic acid derivative with a phenol of the general formula n nHO-A 2 (-A 3 ) n -R′ (III), n nin which A 2 , A 3 , R′ and n are as defined in relation to the formula (I), to give the compound of the formula (I). |