Jianzhuang Jiang

High-performance air-stable ambipolar organic field-effect transistor based on tris(phthalocyaninato) europium(III).

A novel sandwich-type tris(phthalocyaninato) europium triple-decker complex bearing peripheral electron-withdrawing groups (see center of figure) is used to fabricate a field-effect transistor by the quasi-Langmuir-Schaefer method. The air-stable, single-component ambipolar OFET device displays the best carrier properties of a device fabricated by solution processing of a single phthalocyanine derivative so far, which makes the complex very promising for applications in nanoelectronics.

Sandwich-type tetrakis(phthalocyaninato) dysprosium–cadmium quadruple-decker SMM

Homoleptic tetrakis[2,3,9,10,16,17,23,24-octa(butyloxy)phthalocyaninato] dysprosium-cadmium quadruple-decker complex 1 was isolated in relatively good yield of 43% from a simple one-pot reaction. This compound represents the first sandwich-type tetrakis(phthalocyaninato) rare earth-cadmium quadruple-decker SMM that has been structurally characterized.

Rational design and synthesis for versatile FRET ratiometric sensor for Hg2+ and Fe2+: a flexible 8-hydroxyquinoline benzoate linked Bodipy-porphyrin dyad.

A flexible 8-hydroxyquinoline benzoate linked Bodipy-porphyrin dyad has been designed, synthesized, and characterized. Binding of this dyad with Hg(2+)/Fe(2+) induced just the opposite (promoting/restraining) influence on energy transfer from the Bodipy donor to the porphyrin acceptor, resulting in a remarkably different ratio change of two signal emissions, endowing this dyad as the first Bodipy-porphyrin-based versatile fluorescence resonance energy transfer (FRET) ratiometric sensor for Hg(2+) and Fe(2+) ions, respectively.

Binuclear phthalocyanine-based sandwich-type rare earth complexes: Unprecedented two π-bridged biradical-metal integrated SMMs

Mini-magnets: Sandwich-type rare earth complexes involving two fused bis(phthalocyaninato) dysprosium(III) units, represent the first example of biradical-metal single molecule magnets (SMMs). These materials were synthesized and structurally characterized. Comparative investigation reveals the effective suppression of quantum tunneling of magnetization (QTM) by the π-bridged biradical-based antiferromagnetic interaction in the di-dysprosium-ion-based SMM.

Tetrakis(phthalocyaninato) Rare‐Earth–Cadmium–Rare‐Earth Quadruple‐Decker Sandwich SMMs: Suppression of QTM by Long‐Distance f–f Interactions

Long-distance f-f interactions: Systematic and comparative studies of the magnetic properties of a series of isostructural sandwich-type tetrakis(phthalocyaninato) diterbium and monoterbium quadruple-decker complexes clearly reveal the suppression of the quantum tunneling of magnetization by the long-distance intramolecular f-f interactions (see figure).

Organic Semiconductors of Phthalocyanine Compounds for Field Effect Transistors (FETs)

Various functional phthalocyanines as well as their tetrapyrrole analogs, porphyrins, have been extensively studied as organic semiconductors since the first report of organic field effect transistors (OFETs) in 1986. The large conjugated π system, excellent photoelectric characteristics, intriguing and unique optical properties, high thermal and chemical stability, and most importantly the easy functionalization of phthalocyanines render them ideal organic semiconductor materials as active layers for OFETs. In this chapter, the semiconducting properties of monomeric phthalocyanines as well as monomeric porphyrins, bis(phthalocyaninato) rare earth double-deckers, and tris(phthalocyaninato) rare earth triple-deckers in terms of their semiconducting nature (p-type, n-type, or ambipolar), carrier mobility, and current modulation reported in the past two decades have been summarized. Theoretical studies toward understanding the relationship between molecular structures as well as molecular electronic structures of phthalocyanines and their semiconducting properties have also been included.

Morphology and chirality controlled self-assembled nanostructures of porphyrin–pentapeptide conjugate: effect of the peptide secondary conformation

An optically active porphyrin–pentapeptide conjugate 1, actually a porphyrinato zinc complex covalently linked with a glycinyl–alanyl–glycinyl–alanyl–glycine (GAGAG) peptide chain, was designed and synthesized. The self-assembly properties of this novel porphyrin–pentapeptide conjugate in THF/n-hexane and THF/water were comparatively investigated by electronic absorption, circular dichroism (CD), IR spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) technique. Associated with the different secondary conformation of the pentapeptide chain covalently linked to the porphyrin ring in different solvent systems, self-assembly of conjugate 1 leads to the formation of nanofibers with right-handed helical arrangement and nanotubes with left-handed helical arrangement in a stack of porphyrin chromophores according to the CD spectroscopic result in apolar THF/n-hexane (1 : 3) and polar THF/water (1 : 3) system depending on the cooperation between intramolecular or intermolecular hydrogen bonding interaction with chiral discrimination between pentapeptide chains and porphyrin–porphyrin interactions in the direction parallel to the tetrapyrrole ring of neighboring conjugate molecules. IR spectroscopic result clearly reveals the α-helix and β-sheet secondary conformation, respectively, employed by the pentapeptide chain attached at the porphyrin core in the nanostructures formed in THF/n-hexane (1 : 3) and THF/water (1 : 3). The X-ray diffraction (XRD) result confirms that in the nanotubes, a dimeric supramolecular bilayer structure was formed through an intermolecular hydrogen bonding interaction between two conjugate molecules which, as the building block, self-assembles into the target nanostructures. These results clearly reveal the effect of a secondary conformation of pentapeptide chain in the conjugate molecule on the packing mode of porphyrin chromophore, supramolecular chirality, and morphology of the self-assembled nanostructure. The present result represents not only the first example of organic nanostructures self-assembled from a covalently linked porphyrin–pentapeptide conjugate, but more importantly the first effort towards controlling and tuning the morphology and in particular the supramolecular chirality of porphyrin nanostructures via tuning the secondary conformation of peptides in different solvent systems, which is helpful towards understanding, designing, preparing, and mimicking the structure and role of naturally occurring porphyrin–peptide conjugates. In addition, both nanofibers and nanotubes were revealed to show good semiconducting properties.

Synthesis, Structure, and Single‐Molecule Magnetic Properties of Rare‐Earth Sandwich Complexes with Mixed Phthalocyanine and Schiff Base Ligands

Double- and quadruple-decker complexes of rare-earth metals with mixed phthalocyanine and Schiff base ligands have been synthesized and structurally and magnetically characterized. These complexes (see picture: Dy pink, Ca green, N blue, C black) extend the scope of sandwich-type tetrapyrrole-based rare-earth molecular materials.

Magneto-chiral dichroism in chiral mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker SMMs

Two new chiral mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes with both (R)- and (S)-enantiomers were synthesized and structurally characterized. The significant magneto-chiral cross effect revealed for the dysprosium compound suggests the great potential of sandwich-type tetrapyrrole rare earth systems in the research field of magneto-chiral dichroism.

The first solution-processable n-type phthalocyaninato copper semiconductor: tuning the semiconducting nature via peripheral electron-withdrawing octyloxycarbonyl substituents

A series of unsymmetrical phthalocyaninato copper complexes simultaneously incorporating electron-withdrawing and electron-donating substituents at the phthalocyanine periphery Cu{Pc(15C5)[(COOC8H17)6]} (2), Cu{Pc[(adj-15C5)2][(COOC8H17)4]} (3), Cu{Pc[(opp-15C5)2][(COOC8H17)4]} (4), Cu{Pc(15C5)3[(COOC8H17)2]} (5) were prepared and isolated. For comparative studies, symmetrical analogues including 2,3,9,10,16,17,24,25-octakis(octyloxycarbonyl)phthalocyaninato copper complex Cu[Pc(COOC8H17)8] (1) and 2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninato copper complex Cu[Pc(15C5)4] (6) were also prepared. Their electrochemistry was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). With the help of a solution-based self-assembly process, these compounds were fabricated into organic field effect transistors (OFETs) with top contact configuration on hexamethyldisilazane (HMDS)-treated SiO2/Si substrate. In line with the electrochemical investigation results, a p-type OFET with a carrier mobility (for holes) of 0.06 cm2 V−1 s−1 was shown for Cu[Pc(15C5)4] (6) with electron-donating 15-crown-5 as the sole type of peripheral substituent. In contrast, n-type devices with a carrier mobility (for electrons) of 6.7 × 10−6–1.6 × 10−4 cm2 V−1 s−1 were achieved for 1–5 with electron-withdrawing octyloxycarbonyl substituents at the peripheral positions of phthalocyanine ring, indicating the significant effect of electron-withdrawing octyloxycarbonyl substituents on tuning the nature of phthalocyanine organic semiconductors. The present results represent the first example of solution-processed n-type phthalocyanine-based OFET devices.