Synthesis of the monosubstituted ferrocenomesogens

• Main Authors: Cheng-Wen Shen, 沈玟呈
• Other Authors: C. K. Lai
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/40388144708830518363

碩士 === 國立中央大學 === 化學研究所 === 91 === Studies focused on synthesis and mesomorphic properties of ferrocene-based metallomesogens have gained increasing importance in recent years. Ferrocene, because of its aromatic character, facilitates several substitution reactions whereby a range of low molecular mass calamitic (rod-like) systems can be prepared by monosubstitution, disubstitution of 1,1’-, 1,2-, 1, 3-position, or 1,1,3-trisubstitution on the ferrocene molecules. In reported ferrocenyl systems, most liquid-crystalline behaviour has been found to exhibit nematic (N), smectic A (SmA) or smectic C (SmC). The mesomorphic behavior may be due to the size of the ferrocene unit, in which two cyclopendienyl rings sterically interfere with the packing of the molecules, thereby preventing the build-up of long-range order that would result in the formation of a softer crystal phase. We describe herein the synthesis and mesomorphic of the mono substituted ferrocenecontaining liquid crystals. Their mesomorphic properties were investigated by use of polarized optical microscopy and differential scanning calorimetry(DSC). All the prepared compounds exhibit a smectic A mesophase.