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Indexed by:会议论文

Date of Publication:2006-07-01

Page Number:1

Key Words:清亮点;氰基;

Abstract:Liquid Crystal display is used extensively in high technology because of its distinctive features about lightness,thinness,and low power consumption. As the main material of TN-LCD and STN-LCD[1],4-n-alkyl-4’-cyano-p-terphenyl has many advantages,such as their high melting point,wide mesomorphic temperature,photo chemical stabilities and improve the birefringence and multiplexing[2][3]. It is with difficulty that 4-n-alkyl-4’-cyano-p-terphenyl was synthesized and checked for its large molecular weight,high melting point,bad solubility and low reactivity. Alkyl-terphenyl as the raw material in this method reacts with I2 and HIO3 to give 4-alkyl-4’-iodo-p-terpheny,the B reacts with (CuCN)2 to give 4-alkyl-4’-cyano-p-terphenyl,synthetic conditions of each step and purity were studied. Iodination was studied emphatically. Reversible reaction must be avoided to produce iodide. So HI must be removed and iodating agent with strong electrophilicity must be used. The method to remove HI is to add the oxidizer to oxida...