| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new fluorene-based compound useful as a liquid crystal display element suitable for a ferroelectric liquid crystal display element. SOLUTION: This new fluorene-based compound is expressed by formula I [wherein R1 and R2 are each a (substituted) 1-16C alkyl; X is CH2 or CO; Y is a single bond, OCH2, CH2O or the like; A is (substituted) 1,4-phenylene or 1,4-cyclohexylene] and is e.g. 2-pentyl-7-(4-octylphenyl)fluorene. The compound of formula I is obtained by subjecting a fluorene of formula II to Friedel-Crafts reaction, by reducing the reaction product with hydrazine in the presence of a base, by reacting the reaction product with bromine in a solvent such as chloroform and by subjecting the reaction product and a boronic acid derivative to cross coupling reaction in the presence of a catalyst such as palladium.
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