3,3'-Bis(4'-R-4-stilbenyl)oxyalkyloxybiphenyl-4,4'-diamine and preparing method thereof

摘要

PURPOSE: A 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|biphenyl-4,4-diamine, its preparation method, an aromatic polyimide and a liquid crystal display device using the polyimide are provided, wherein the diamine compound is useful as a monomer for preparing a polyamide or polyimide, aromatic polyimide has an improved solubility for an organic solvent, and LCD device is improved in a free tilt angle characteristic. CONSTITUTION: The 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|biphenyl-4,4-diamine is represented by the formula 1, wherein R is a halogen atom, CN, CF3, OCjH2j+1 or CjH2j+1 (wherein j is an integer of 2-12); and m is an integer of 2-12. The method comprises the steps of reacting 3,3-dihydroxy-4,4-diphthalimidobiphenyl with (4-R-4-stilbenyl)oxyalkan-1-ol to obtain 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|-4,4-diphthalimidobiphenyl by the Mitsunobu reaction; and hydrolyzing 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|-4,4-diphthalimidobiphenyl to obtain 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|biphenyl-4,4-diamine. Preferably the Mitsunobu reaction is carried out in the presence of triphenylphosphine and diethyl azodicarboxylate, and the hydrolysis is carried out in the presence of hydrazine monohydrate. The aromatic polyimide is prepared by using the 3,3-bis£(4-R-4-stilbenyl)oxyalkyloxy|biphenyl-4,4-diamine of the formula 1, and is represented by the formula 2, wherein Z is selected from the group consisting of following four formulas; R is a halogen atom, CN, CF3, OCjH2j+1 or CjH2j+1 (wherein j is an integer of 2-12); m is an integer of 2-12; and n is an integer of 10-100.