de la Escosura et al.
FIGURE 1. Components for the liquid-crystalline phthalocyanine-C60 blends.
in the literature many examples of liquid crystals formed by
either phthalocyanine6 or fullerene7 derivatives. However, to
the best of our knowledge, mesogenic Pc-C60 dyads have never
been reported, most probably due to the tedious purification of
the unsymmetrically substituted phthalocyanines when they
possess long hydrocarbon chains at the periphery, which is a
structural requirement to induce mesomorphism on this class
of discotic molecules. Moreover, a bulky unit such as C60 cannot
be easily accommodated into a LC columnar organization.
The use of blends, in which a mesogen induces mesomor-
phism to a non-mesogenic compound, represents an elegant
strategy to overcome this problem.8 Herein, we describe for the
first time the organization of Pc-C60 dyads within liquid-
crystalline phases. In this study, a hexagonal columnar phase
was obtained by simply blending either compounds 1, 2, or 3,
bearing at the periphery butoxy, propylsulfonyl, and tert-butyl
substituents, respectively, with the discotic mesogen Zn(II)-
octakis(hexadecylthio)phthalocyanine (4) (Figure 1). Different
types of substituents (electron donor butoxy, electron deficient
propylsulfonyl, bulky tert-butyl groups) have been introduced
at the periphery of the Pc moiety of the dyad to establish their
influence in the final organization within the blend. Although
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