Synthesis of mesogenic phthalocyanine-C₆₀ donor–acceptor dyads designed for molecular heterojunction photovoltaic devices

Abstract

SummaryA series of phthalocyanine-C60 dyads 2a–d was synthesized. Key steps in their synthesis are preparation of the low symmetry phthalocyanine intermediate by the statistical condensation of two phthalonitriles, and the final esterification of the fullerene derivative bearing a free COOH group. Structural characterization of the molecules in solution was performed by NMR spectroscopy, UV–vis spectroscopy and cyclic voltammetry. Preliminary studies suggest formation of liquid crystalline (LC) mesophases for some of the prepared dyads. To the best of our knowledge, this is the first example of LC phthalocyanine-C60 dyads.

Discotic liquid crystals of transition metal complexes 52: Synthesis and homeotropic alignment of liquid crystalline phthalocyanine-fullerene dyad bridged by vanillin

“…As far as we know, the first liquid crystals based on phthalocyanine fullerene (Pc-C 60 ) dyad ( Fig. 1[A]) were reported by our group in 2006 [10][11][12][13][14][15][16][17][18][19][20][21][22] and then Geerts group in 2009 [14]. Among our liquid crystalline Pc-C 60 dyads, we found at the first time in 2006 that some of the Pc-C 60 dyads exhibit perfect homeotropic alignment between two glass plates ( Fig.…”

“…1[C]). Furthermore, the (C n S) 6 PcCu-C m -C 60 dyads (2a-c) exhibit homeotropic alignment at rt for (n, m) = (14,8), (14,10), (14,12). Hence, the donor part of hexakistetradecyllthio-substituted PcCu, (C 14 S) 6 PcCu-, may be favourable to induce a room temperature liquid crystalline phase.…”

Discotic liquid crystals of transition metal complexes 48: Synthesis of novel phthalocyanine-fullerene dyads and effect of a methoxy group on their clearing points

“…They can greatly reduce their costs to manufacture the solar cells. Liquid crystalline D-A systems are braodly classified into three groups: smectic liquid crystals [1][2][3][4], liquid crystalline copolymers [5][6][7][8][9][10][11][12] and discotic columnar liquid crystals [13][14][15][16][17][18][19][20][21][22][23][24][25]. In 2004 Kim et al reported that an organic photovoltaic cell was fabricated by using liquid crystalline N,N'-diheptyl-3,4,9,10-perylenetetracarboxylicdiimide (PTCDI-C7) as the electron acceptor and zinc phthalocyanine (ZnPc) as the electron donor [1].…”

Side chain polysiloxanes with phthalocyanine moieties

“…The result implies that the attachment of Pc via flexible spacer to the flexible polysiloxane does not preclude self-assembling of phthalocyanine discs. It is worth noting that the enthalpy of the phase transitions at 70.8 and 32.7°C is much higher than usually observed for transitions of alkylated phthalocyanines from liquid crystalline state to isotropic melt and reverse [14,16,17]. It suggests the crystalline (not liquid crystalline) nature of Polymer 1.…”