The present invention relates to a process for the preparation of a compound of the general formula R-(A1-Z-)mB—CF2O-A2-(A3)n-R′  (I) in which R is alkyl, in which one or more CH2 groups may be replaced, independently of one another, by O, CF2, CH═CH, CH═CF or CF═CF, with the proviso that peroxide structures O—O and formaldehyde acetals O—CH2—O are excluded, A1 is, independently of one another, 1,4-cyclohexylene, 2,5-1,3-dioxanylene, 1,3-cyclobutylene or A2 and A3 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, —CH2—CH2—, —CF2—CF2—, —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, OCF3, OCF2H, CF3, CI, SF5, 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 R-(A1-Z-)mBX   (II), in 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 HO-A2(-A3)n-R′  (III), in which A2, A3, R′ and n are as defined in relation to the formula (I), to give the compound of the formula (I).