Building molecules: molecular engineering - Molecular Organic Materials - page 99

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Figure 2.16. TTF 21 -glycol dendrimer obtained with the method of deprotec-
tion/alkylation of cyanoethyl-protected TTF-thiolates described in Fig. 2.15
(Christensen et al. , 1998).

C 60 -TTF molecules, interlocked molecules (catenanes, rotaxanes), donor-acceptor
macrocycles, cage molecules, etc. (Jeppesen et al. , 2004). It is beyond the scope of
this topic to review such developments and I appeal to the curiosity of researchers
really not familiar with such macromolecules to see how big the molecules can
become.
One astute way to obtain macrocyclic systems with TTF is the stepwise method
of deprotection/alkylation of cyanoethyl-protected TTF-thiolates. With this method
molecular units can be built but with the precaution of preserving one cyanoethyl
group in order to be able to iteratively proceed with the oligomerization. Combining
such units, larger units can be produced. An example of a TTF dendrimer containing
21 TTFs is shown in Fig. 2.15 (Christensen et al. , 1998). Here only the main
philosophy of the synthesis is discussed.