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The use of blen
ds in which a mesogen in
duces mesomorphism into a non-mesogenic compoun
d hasma
de possible the self-organization of phthalocyanine-[60]fullerene (Pc-C
60)
dya
ds into liqui
d crystals.Pc-C
60 dya
ds
1,
2, or
3, in which two photoactive units are brought together by a phenylenevinylenespacer, have been synthesize
d through a Heck reaction that links 4-vinylbenzal
dehy
de to a monoio
dophthalocyanine precursor, followe
d by stan
dar
d cycloa
ddition of azomethine yli
des-generate
d from theformylPc
derivative an
d N-methylglycine-to one of the
double bon
ds of C
60. The mesomorphic an
dthermal properties of
different mixtures forme
d by the liqui
d-crystalline phthalocyanine
4 an
d dya
ds
1,
2, or
3 were examine
d using polarizing optical microscopy (POM),
differential scanning calorimetry(DSC), an
d X-ray
diffraction (XRD). DSC
diagrams of the blen
ds show clear transitions from the crystallinestate to a mesophase, an
d the measure
d structural parameters obtaine
d from the pow
der
diffractionexperiments are consistent with a
discotic hexagonal columnar (Col
h) structure. Consi
dering that segregationin
domains of separate
d molecules of Pc-C
60 dya
d an
d phthalocyanine
4 woul
d preclu
de mesomorphism
due to the mismatch in the column
diameter an
d to the lack of mesogenic character of the pure
dya
ds,a pre
dominance of alternating stacking is propose
d. A
dditionally, the observe
d decrease in the calculate
ddensity of the blen
d mesophases relative to the mesophase of pure compoun
d 4 is important evi
dence inthis
direction.