Dongdong Qi

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.

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.

Density functional theory studies on the structures and electronic communication of meso-ferrocenylporphyrins: Long range orbital coupling via porphyrin core

The molecular and electronic structures together with the electronic absorption spectra of a series of metal free meso-ferrocenylporphyrins, namely 5-ferrocenylporphyrin (1), 5,10-diferrocenylporphyrin (2), 5,15-diferrocenylporphyrin (3), 5,10,15-triferrocenylporphyrin (4), and 5,10,15,20-tetraferrocenylporphyrin (5) have been studied with the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods. For the purpose of comparative studies, metal free porphyrin without any ferrocenyl group (0) and isolated ferrocene (6) were also calculated. The effects of the number and position of meso-attached ferrocenyl substituents on their molecular and electronic structures, atomic charges, molecular orbitals, and electronic absorption spectra of 1-5 were systematically investigated. The orbital coupling is investigated in detail, explaining well the long range coupling of ferrocenyl substituents connected via porphyrin core and the systematic change in the electronic absorption spectra of porphyrin compounds.

Porphyrin–Alkaline Earth MOFs with the Highest Adsorption Capacity for Methylene Blue

A series of four porphyrin-alkaline earth metal- organic frameworks [Mg(HDCPP)2 (DMF)2 ]n ⋅(H2 O)7 n (1), [Ca(HDCPP)2 (H2 O)2 ]n (DMF)1.5 n (2), [Sr(DCPP)(H2 O)(DMA)]n (3), and [Ba(DCPP)(H2 O)(DMA)]n (4) was isolated for the first time from solvothermal reaction between metal-free 5,15-di(4- carboxyphenyl)porphyrin (H2 DCPP) and alkaline earth ions. Single-crystal X-ray diffraction analysis reveals the 2D and 3D supramolecular network with periodic nanosized porosity for 1/2 and 3/4, respectively. The whole series of MOFs, in particular, compounds 1 and 2 with intrinsic low molecular formula weight, exhibit superior adsorption performance for methylene blue (MB) with excellent capture capacity as represented by the thus far highest adsorption amount of 952 mg g(-1) for 2 and good selectivity, opening a new way for the potential application of the main group metal-based MOFs.

A Chiral Phthalocyanine Dimer with Well‐Defined Supramolecular Symmetry Based on π–π Interactions

Cooperation is the name of the game: The first example of a chiral phthalocyanine dimer with well-defined supramolecular weight and symmetry formed through cooperative multiple π-π interactions among nine pairs of aromatic moieties between two chiral phthalocyaninato zinc molecules has been clarified (see figure).

Co-crystallized fullerene and a mixed (phthalocyaninato)(porphyrinato) dysprosium double-decker SMM

Effective and different inter-molecular interactions between fullerene C60 and tetrapyrrole-based double-decker single molecule magnets (SMMs) of three cocrystallates with different molar ratios rationalize the slight structural changes and different magnetic properties. The presented results indicate that different integration modes between the SMM and conjugated sp2-carbon substrate are able to affect the magnetic properties of the spintronic devices to different degrees, representing the effort towards understanding the effect of the conjugated sp2-carbon substrate on the magnetic properties of SMM spintronic devices at a molecular level.

Boron–Phenylpyrrin Dyes: Facile Synthesis, Structure, and pH‐Sensitive Properties

Boron-phenylpyrrin dyes: In the presence of BF3⋅OEt2, 4-(diethylamino)salicylaldehyde reacts with substituted pyrroles to give boron-phenylpyrrin dyes, which contain a central boron-containing seven-membered ring. Upon protonation in acidic solution, the complexes, with a large Stokes shift, exhibit a color change and a unique red shift in both the electronic absorption and fluorescence emission spectra (see picture), thus rendering them new analogues of boron-dipyrrin dyes that can be used as pH sensors.

2,3,9,10,16,17,23,24-Octakis(hexylsulfonyl)phthalocyanines with good n-type semiconducting properties. Synthesis, spectroscopic, and electrochemical characteristics

The synthesis of peripherally octa-substituted phthalocyanine compounds with eight strong electron-withdrawing hexylsulfonyl groups was systematically studied. Three new phthalocyanines M[Pc(SO2C6H13)8] [Pc(SO2C6H13)8 = 2,3,9,10,16,17,23,24-octakis(hexylsulfonyl)phthalocyaninate; M = 2H (1), Cu (2), Zn (3)] were synthesized via direct cyclic tetramerization of 4,5-di(hexylsulfonyl)phthalonitrile or through a diiminoisoindoline intermediate. Compounds 1–3 could alternatively be prepared by oxidation of the hexylthio substituents in corresponding 2,3,9,10,16,17,23,24-octakis(hexylthio)phthalocyanine compounds M[Pc(SC6H13)8] (M = 2H, Cu, Zn) with m-chloroperbenzoic acid. They were fully characterized by elemental analysis and a series of spectroscopic methods. Their electrochemistry was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Density function theory (DFT) calculations were conducted to study the effect of the strong electron-withdrawing groups on the electronic structure of the phthalocyanine molecules. Particularly, the first reduction potentials in the range −0.30∼−0.04 V vs. the saturated calomel electrode (SCE) for 1–3 reveal their n-type semiconducting nature. The current–voltage characteristics of their aggregates demonstrate the good semiconducting properties especially for 1 and 2 with the conductivity value of 5.24 × 10−4 and 2.73 × 10−4 S m−1, respectively.

Four Dibutylamino Substituents Are Better Than Eight in Modulating the Electronic Structure and Third-Order Nonlinear-Optical Properties of Phthalocyanines.

2(3),9(10),16(17),23(24)-Tetrakis(dibutylamino)phthalocyanine compounds M{Pc[N(C4H9)2]4} (1-5; M = 2H, Mg, Ni, Cu, Zn) were prepared and characterized by a range of spectroscopic methods in addition to elemental analysis. Electrochemical and electronic absorption spectroscopic studies revealed the more effective conjugation of the nitrogen lone pair of electrons in the dibutylamino side chains with the central phthalocyanine π system in M{Pc[N(C4H9)2]4} than in M{Pc[N(C4H9)2]8}, which, in turn, results in superior third-order nonlinear-optical (NLO) properties of H2{Pc[N(C4H9)2]4} (1) over H2{Pc[N(C4H9)2]8}, as revealed by the obviously larger effective imaginary third-order molecular hyperpolarizability (Im{χ((3))}) of 6.5 × 10(-11) esu for the former species than for the latter one with a value of 3.4 × 10(-11) esu. This is well rationalized on the basis of both structural and theoretical calculation results. The present result seems to represent the first effort toward directly connecting the peripheral functional substituents, electronic structures, and NLO functionality together for phthalocyanine molecular materials, which will be helpful for the development of functional phthalocyanine materials via molecular design and synthesis even through only tuning of the peripheral functional groups.

Linkage Dependence of Intramolecular Fluorescence Quenching Process in Porphyrin-Appended Mixed (Phthalocyaninato)(Porphyrinato) Yttrium(III) Double-Decker Complexes

Three novel mixed (phthalocyaninato)(porphyrinato) yttrium double-decker complexes appended with one metal-free porphyrin chromophore at the para, meta, and ortho position, respectively, of one meso-phenyl group of the porphyrin ligand in the double-decker unit through ester linkage, 3-5, have been designed, synthesized, and spectroscopically characterized. The photophysical properties of these three isomeric tetrapyrrole triads were comparatively investigated along with the model compounds metal-free tetrakis(4-butyl)porphyrin H(2)TBPP (1) and mixed [1,4,8,11,15,18,22,25-octakis(butyloxyl)phthalocyaninato][tetrakis(4-butyl)porphyrinato] yttrium double-decker complex HY[Pc(α-OC(4)H(9))(8)](TBPP) (2) by steady-state and transient spectroscopic methods. The fluorescence of the metal-free porphyrin moiety attached through ester linkage at the meta and ortho position of one meso-phenyl group of porphyrin ligand in the double-decker unit in triads 4 and 5 is effectively quenched by the double-decker unit, which takes place in several hundred femtoseconds. However, the fluorescence of the metal-free porphyrin moiety attached at the para position of one meso-phenyl group of porphyrin ligand in the double-decker unit in triad 3 is only partially quenched, clearly revealing the effect of the position of porphyrin-substituent on the photophysical properties of the triads. Furthermore, the molecular structures of 3-5 were simulated using density functional theory calculations. It was found that the relative orientation between the metal-free porphyrin moiety and the double-decker unit for compound 3 is crossed, while those for compounds 4 and 5 are open- and closed-shellfish-like, respectively, which is suggested to be responsible for their different intramolecular fluorescent quenching efficiency.