Complimentary Polytopic Interaction

Bushby et al. were able to access similar AB stacks with derivatives of 25 using aromatic units, which are not electron-poor [86-88]. They showed that hexakis(4-nonylphenyl)triphenylene (28, n = 8) forms alternating stacks with 25 (Fig. 13). Unlike the electron-deficient derivatives mentioned previously, which exhibit single liquid crystal phases over a wide composition range of the two components, phase separation between the 25 28 and the 25 or 28 mesogenic phases occurs [89]. The driving force for the AB stack formation is a combination of a number of different non-covalent interactions which the authors termed complimentary polytopic interactions (CPIs). 

Fig. 13 Self-assembly of alternating stacks can be achieved with an electron-rich 25 and electron-poor 26 or mellitic triimde 27. Alternatively, complimentary polytopic interactions (CPI) can be used to organize 25 and 28 as shown, yielding the desired assemblies...

Fig. 8.5 Chemical structures of two types of triphenylene derivatives for Complimentary Polytopic Interaction (CPI) studies toward highly efBcient charge transptnt...

A well-studied binary system of discotic liquid crystal toward high carrier mobility systems is a blend of two types of triphenylene-based compounds (Fig. 8.5). These two compounds were mixed in expectation to give a new semiconducting system that exhibits enhancement of charge transport efficiency. The concept is based on Complimentary Polytopic Interaction (CPI) [16-18]. 

The first liquid crystalline derivatives of HAT were reported by Bushby and coworkers [90-92]. They prepared several hexaphenyl-substituted HAT derivatives 48 with different peripheral chains as shown in Scheme 4.13. It is worth noting that some non-mesomorphic HAT derivatives when mixed with other discotic liquid crystals, exhibit stable columnar phases due to complimentary polytopic interactions [90, 91],... 

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