2D and 3D Nets by Self‐Assembly of Carbosilane Functionalized Polyphilic Liquid Crystals

Abstract

Herein we report new liquid crystalline (LC) compounds with highly branched carbosilane chains. The considered compounds are so‐called bolapolyphiles, consisting of a rigid p ‐terphenyl core with two sticky glycerol groups at both ends and a bulky branched carbosilane side‐chain. With growing side‐chain volume, a transition from rectangular via square and pentagonal to hexagonal honeycombs and finally to an intercalated 3D network formed by enantiomorphic (10,3)‐a nets and Ia d space group was observed. The obtained series of LC phases is compared with those of related compounds with linear side‐chains. Because the branched carbosilanes provide a larger chain volume than linear with the same length, they tend to form larger honeycomb cells. However, as the chains remain too short to reach and fill the centers of these larger cells, at a certain limit of chain volume and temperature, the honeycomb is broken up and transformed into a 3D network. The observed honeycombs and network structures are compared with related structures of inorganic solid‐state materials and discussed in relation to the concept of “mesoatoms,” with the laterally attached carbosilane side‐groups determining their valence and coordination geometry.