| 摘要 |
A diaminobenzene derivative is provided to align liquid crystals uniformly and vertically, to exhibit excellent mechanical characteristics such as heat resistance and surface strength, to have a high free-tilt angle, and to increase response time of liquid crystal. A diaminobenzene derivative represented by the chemical formula 1 is prepared by the steps of: (a) reacting a compound of the chemical formula 2 with 1-bromo-4-(3-tert-butoxy-alkyl)-benzene, tetrakis(triphenylphosphine) palladium, cesium fluoride, and 1,2-dimethoxy-ethane to prepare a compound of the chemical formula 3; (b) reacting the compound of the chemical formula 3 with acetic acid and bromic acid, followed by reacting the resultant with potassium carbonate and methanol to prepare a compound of the chemical formula 4; (c) reacting the compound of the chemical formula 4 with triethylamine, tetrahydrofuran, 3,5-dinitrobenzoyl chloride to prepare a compound of the chemical formula 5; and (d) subjecting the compound of the chemical formula 5 to hydrogen reduction in the presence of a Pd/C catalyst and isolating a trans-isomer compound from the resultant. In the chemical formulae, n is an integer of 1-5, and R is a C3-5 alkyl group or alkoxy group. |
