The divergent synthesis of a novel pentaerythritol-based carbosilane liquid crystalline dendrimer PCSi-3G-NO₂ was described. A terminal Si—Cl functional carbosilane dendrimer of the third generation based on pentaerythritol was used as dendritic scaffold and subsequently functionalized with 4-nitroazobenzene (M-NO₂). Structure and properties of PCSi-3G-NO₂ were characterized by elemental analysis, ¹H NMR, IR, polarizing optical microscopy (POM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). PCSi-3G-NO₂ is cholesteryl and smectic E liquid crystal, different from the mesogenic unit M-NO₂ that shows nematic phase. They are different in terms of the melting point, the clearing point and the temperature region of mesogenic phase.

Key words: carbosilane liquid crystalline dendrimer, pentaerythritol, 4-nitroazobenzene, dendrimer of the third generation, mesogenic group