Synthesis and Physical Properties of Ferrocene Derivatives (XVIII): Crystal Structure of a Liquid-Crystalline Ferrocene Derivative, 10-[4-(4-Methoxyphenoxycarbonyl)phenoxycarbonyl]decyl 4-Ferrocenylbenzoate

Abstract

The molecular and crystal structures of the title compound, which exhibited smectic C and nematic phases, have been determined by direct methods using single-crystal X-ray diffraction data. The structure was orthorhombic with the space group Pbca and Z = 8. The two cyclopentadienyl rings were an eclipsed conformation, and the flexible spacer was an all-trans conformation, but the molecule was slightly bow-shaped. Additionally, the molecules were packed in an antiparallel fashion, and two molecules had become a pair except for a ferrocenyl moiety. The molecules were in a head-to-head arrangement between contiguity layers and formed a layer structure similar to that of a smectic one. Also, dipole–dipole interaction of carbonyl groups was seen between neighboring molecules.

Keywords:

• crystal structure
• ferrocene
• liquid crystal
• metallomesogen
• monosubstituted ferrocene derivative

ACKNOWLEDGMENT

A High-Tech Research Center Project for Private Universities matching fund subsidy from MEXT (Ministry of Education, Culture, Sports, Science and Technology), 2002–2005, is gratefully acknowledged for partial support of the present work. We are grateful to K. Uno, Department of Chemistry, Ritsumeikan University, Japan, for the technical support of the X-ray instrument.