Houhe Pan

Unsymmetrical Pyrene-Fused Phthalocyanine Derivatives: Synthesis, Structure, and Properties

Novel pyrene-fused unsymmetrical phthalocyanine derivatives 2,3,9,10,16,17-hexakis(2,6-dimethylphenoxy)-22,25-diaza(2,7-di-tert-butylpyrene)[4,5]phthalocyaninato zinc complex Zn[Pc(Pz-pyrene)(OC8 H9 )6 ] (1) and 2,3,9,10-tra(2,6-dimethylphenoxy)-15,18,22,25-traza(2,7-di-tert-butylpyrene)[4,5]phthalocyaninato zinc compound Zn[Pc(Pz-pyrene)2 (OC8 H9 )4 ] (2) were isolated for the first time. These unsymmetrical pyrene-fused phthalocyanine derivatives have been characterized by a wide range of spectroscopic and electrochemical methods. In particular, the pyrene-fused phthalocyanine structure was unambiguously revealed on the basis of single crystal X-ray diffraction analysis of 1, representing the first structurally characterized phthalocyanine derivative fused with an aromatic moiety larger than benzene.

A post-cyclotetramerization strategy towards novel binuclear phthalocyanine dimers

A new and efficient post-cyclotetramerization strategy was developed for the synthesis of binuclear phthalocyanine dimers sharing one common pyrazine moiety, for the first time, paving a new way towards the design and synthesis of novel conjugated oligomeric phthalocyanine derivatives with various application potentials.

Phenanthro[4,5-fgh]quinoxaline-Fused Subphthalocyanines: Synthesis, Structure, and Spectroscopic Characterization.

A series of four phenanthro[4,5-fgh]quinoxaline-fused subphthalocyanine derivatives 0-3 containing zero, one, two, and three phenanthro[4,5-fgh]quinoxaline moieties, respectively, were isolated from the mixed cyclotrimerization reaction of 2,9-di-tert-butylphenanthro[4,5-fgh]quinoxaline-5,6-dicarbonitrile with 4,5-bis(2,6-diisopropylphenoxy)phthalonitrile and characterized by a series of spectroscopic methods including MALDI-TOF mass, (1) H NMR, electronic absorption, magnetic circular dichroism (MCD), and fluorescence spectroscopy. The molecular structures for the compounds 0 and 2 were clearly revealed on the basis of single-crystal X-ray diffraction analysis. Their electrochemical properties were also studied by cyclic voltammetry. In particular, theoretical calculations in combination with the electronic absorption and electrochemical analyses revealed the significant influence of the fused-phenanthro[4,5-fgh]quinoxaline units on the electronic structures.

Towards Clarifying the Role of O2 during the Phthalocyanine Synthesis

The role of O2 within the synthesis of phthalocyanines (Pcs) has remained unclear in the past century. Here, we demonstrate that O2 , in cooperation with the solvent n-pentanol, participates in the cyclic tetramerization of phthalonitriles over the half-sandwich complex template [Lu(Pc)(acac)] (acac=acetylacetonate) and terminates the reaction at the stage of uncyclized isoindole oligomeric derivatives rather than the phthalocyanine chromophores, resulting in the isolation of the heteroleptic (phthalocyaninato)(triisoindole-1-one) lutetium double-decker complexes [(Pc)Lu(TIO-I)] (TIO-I=3,4,7,8,11,12-sexi(2,6-diisopropylphenoxy)-15-[4,5-di(2,6-diisopropylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) and [(Pc)Lu(TIO-II)] (TIO-II=3,4,7,8,11,12-sexi(2,6-dimethylphenoxy)-15-[4,5-di(2,6-dimethylphenoxy)-2-cyanobenzimidamido]triisoindole-1-one) with the help of bulky substituents at the phthalonitrile periphery and an unsubstituted phthalocyanine ligand in the double-decker skeleton. Nevertheless, the cyclic tetramerization of the phthalonitriles was revealed to be sensitive to O2 with the reaction progression also depending on the oxygen concentration/content, leading to the O2 -senstive and -dependent nature for the isolation of phthalocyanine derivatives.

An ethynyl-linked Fe/Co heterometallic phthalocyanine conjugated polymer for the oxygen reduction reaction

The Sonogashira–Hagihara coupling reaction is utilized to fabricate ethynyl-linked phthalocyanine (Pc) 2D conjugated polymers (CPs), affording the unprecedented heterometallic compound Fe0.5Co0.5Pc-CP and homometallic analogues MPc-CPs (M = Fe, Co) for comparison. It is confirmed that Fe and Co ions are well-defined/distributed with one metal ion encircled by four neighboring ions of the second metal in close proximity in the heterometallic conjugated polymer. Compared to the homometallic analogues, the bimetallic polymer Fe0.5Co0.5Pc-CP is more highly efficient for the oxygen reduction reaction (ORR), indicating that the interaction of Fe and Co ions may provide a synergistic effect on the activity. Fe0.5Co0.5Pc-CP exhibits similar ORR catalytic activity and superior stability compared to commercial Pt/C in alkaline media. Density functional theory calculations reveal that a fast 2 × 2e− synergistic catalytic reaction pathway is essential for the excellent ORR in Fe0.5Co0.5Pc-CP.

Hemiporphyrazine-Involved Sandwich Dysprosium Double-Decker Single-Ion Magnets

Both heteroleptic (phthalocyaninato)(hemiporphyrazinato) and homoleptic bis(hemiporphyrazinato) dysprosium double-decker complexes, Dy[H(Hp)2] (1) and Dy[H(Pc)(Hp)] (2) (H2Pc = metal-free phthalocyanine; H2Hp = metal-free hemiporphyrazine), were designed, synthesized, and structurally characterized. The dysprosium center in both double-deckers are octa-coordinated with a nearly ideal square-antiprismatic coordination geometry, which provides an increased molecular anisotropy for the dysprosium ion and ensures the strengthened magnetic properties of both single-ion magnets (SIMs) in terms of coordination geometry. Magnetic studies reveal that both double-deckers exhibit typical SIM behavior with a spin reversal energy barrier of 80.1 ± 6.3 K for 1 and 57.3 ± 3.8 K for 2 as well as the hysteresis loops emerging at 3 K. In particular, introduction of two Hp ligands with four pyridine nitrogen atoms coordinated with the dysprosium spin center endows Dy[H(Hp)2] (1) with the thus far highest energy barrier among the sandwich-type dysprosium SIMs with N4-macrocyclic ligands, revealing the potential applications of sandwich-type lanthanide complexes with Hp ligands in molecular-based information storage.

Novel, linear oligoisoindole compounds with a conjugated electronic structure

Unprecedented linear oligoisoindole derivatives including diisoindole, triisoindole, tetraisoindole, and hexaisoindole species, representing the new family rather than the traditional cyclic oligoisoindole ones, have been synthesized and spectroscopically characterized for the first time. Variable temperature NMR experiments in combination with DFT calculations reveal the tautomerization of the N–H protons between the outer and inner isoindole units in triisoindole, tetraisoindole, and hexaisoindole species at room temperature. The conjugated electronic structure nature of these oligoisoindole compounds has been clearly clarified on the basis of their single crystal molecular structure, electronic absorption, fluorescence, and electrochemical properties together with theoretical calculations. Moreover, the π Mayer bond order calculation suggests that these oligoisoindole compounds have two types of strong conjugated regions including the delocalized conjugated line across the whole skeleton and the localized conjugated circles at the benzene moieties, which are united together into a whole conjugated system by weak π linking bonds. In particular, the π bonds that pervade over all the linear conjugated oligoisoindole skeletons are comparable to those in the traditional cyclic oligoisoindole skeletons. This, in combination with the existence of the well-defined coordination moiety/moieties for these linear oligoisoindoles, suggests their promising application potential in diverse fields including sensors and electronic devices as their cyclic counterparts.