| abstract |
The present invention provides a difluoromethyl ether derivative which shows various suitable physical properties as a liquid crystal compound, a liquid crystal composition comprising the compound and a liquid crystal display element containing the composition, and also provides a simple and efficient process for producing the difluoromethyl ether derivative. n According to the present invention, the process for producing a difluoromethyl ether derivative represented by Formula (1d): n n n wherein R 1 and R 2 each independently represent hydrogen, halogen, a cyano group or an alkyl group having 1 to 20 carbon atoms, in which at least one —CH 2 — may be substituted with —O—, —S—, —CH═CH— or —C≡C— but —O— is not adjacent to another —O—, and in which any hydrogen may be substituted with fluorine; n rings A 1 , A 2 , A 3 and A 4 each independently represent a 1,4-cyclohexylene group in which at least one —CH 2 — may be substituted with —O— or —S—, or a 1,4-phenylene group in which at least one ═CH— may be substituted with ═N— and at least one hydrogen on the ring may be substituted with fluorine, a cyano group or an alkyl group having 1 to 10 carbon atoms; n Z 1 , Z 2 , Z 3 and Z 4 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms, in which at least one —CH 2 — may be substituted with —O—, —S—, —CH═CH— or —C≡C— but —O— is not adjacent to another —O—, and in which any hydrogen may be substituted with fluorine; n Y 1 , Y 2 , Y 3 and Y 4 each independently represent hydrogen, halogen, a cyano group or an alkyl group having 1 to 10 carbon atoms; and n k, l, m and n each independently represent 0 or 1; n is characterized by using an α,α-difluorocyclohexylidene derivative represented by Formula (1a): n n n wherein R 1 , rings A 1 and A 2 , Z 1 , Z 2 , k and l have the same meanings as defined above; as a starting material. |