Hailong Wang

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.

Sandwich-type mixed tetrapyrrole rare-earth triple-decker compounds. Effect of the coordination geometry on the single-molecule-magnet nature.

Employment of the raise-by-one step method starting from M(TClPP)(acac) (acac = monoanion of acetylacetone) and [Pc(OPh)8]M[Pc(OPh)8] led to the isolation and free modulation of the two rare-earth ions in the series of four mixed tetrapyrrole dysprosium sandwich complexes {(TClPP)M[Pc(OPh)8]M[Pc(OPh)8]} [1-4; TClPP = dianion of meso-tetrakis(4-chlorophenyl)porphyrin; Pc(OPh)8 = dianion of 2,3,9,10,16,17,23,24-octa(phenoxyl)phthalocyanine; M-M = Dy-Dy, Y-Dy, Dy-Y, and Y-Y]. Single-crystal X-ray diffraction analysis reveals different octacoordination geometries for the two metal ions in terms of the twist angle (defined as the rotation angle of one coordination square away from the eclipsed conformation with the other) between the two neighboring tetrapyrrole rings for the three dysprosium-containing isostructural triple-decker compounds, with the metal ion locating between an inner phthalocyanine ligand and an outer porphyrin ligand with a twist angle of 9.64-9.90° and the one between two phthalocyanine ligands of 25.12-25.30°. Systematic and comparative studies over the magnetic properties reveal magnetic-field-induced single-molecule magnet (SMM), SMM, and non-SMM nature for 1-3, respectively, indicating the dominant effect of the coordination geometry of the spin carrier, instead of the f-f interaction, on the magnetic properties. The present result will be helpful for the future design and synthesis of tetrapyrrole lanthanide SMMs with sandwich molecular structures.

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).

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: Dyu2005pink, Cau2005green, Nu2005blue, Cu2005black) 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.

Synthesis, crystal structures, and luminescence properties of seven tripodal imidazole-based Zn/Cd(II) coordination polymers induced by tricarboxylates

Seven tripodal imidazole-based metal coordination polymers, [Zn3(L1)2(tib)2]n·(H2O)4n (1), [Cd3(L1)2(tib)2(H2O)2]n·(H2O)6n (2), [Zn3(L2)2(tib)2]n·(H2O)n (3), [Cd3(L2)2(tib)2]n·(H2O)6n (4), [Zn3(L3)2(tib)2]n·(H2O)4.5n (5), [Zn2(HL3)2(tib)2]n·(H2O)n (6), and [Cd3(L3)2(tib)2(H2O)2]n·(H2O)4n (7), with different structures have been designed and prepared based on the hydrothermal reaction between Zn(OAc)2·2H2O or Cd(OAc)2·2H2O and tib ligands in the presence of three asymmetric semi-rigid V-shaped tricarboxylate ligands, H3L1–3, where tib, H3L1, H3L2, and H3L3 ligands represent 1,3,5-tris(1-imidazolyl)benzene, 3-(2-carboxyphenoxy)phthalic acid, 4-(2-carboxyphenoxy)phthalic acid, and 3-(4-carboxyphenoxy)phthalic acid, respectively. All of these compounds, sharing three-dimensional (3D) networks, have been clearly identified by single crystal X-ray diffraction analysis. Among complexes 1–7 (except 6), the common 3D skeletons are composed of tib N-donor ligands bridging two-dimensional (2D) sheets made of L1–3 ligands and metal ions. Compound 6 also exhibits a 3D network constructed from partly deprotonated L3 ligands attached to right- and left-helices made of tib ligands and Zn ions. In these compounds, the diversity of the tib ligand-based metal building units is tuned by the molecular conformation of the tricarboxylates and the coordination geometry of the metal ion. In addition, the thermal stability and emission spectroscopy for the series of seven complexes have also been investigated.

Mixed (Phthalocyaninato)(Porphyrinato) Rare Earth Double-Decker Complexes with C4 Chirality: Synthesis, Resolution, and Absolute Configuration Assignment

Mixed (phthalocyaninato)(porphyrinato) rare earth double-decker complexes [HM(III){Pc(alpha-3-OC(5)H(11))(4)}{TOAPP}] [Pc(alpha-3-OC(5)H(11))(4) = 1,8,15,22-tetrakis(3-pentyloxy)-phthalocyaninate; TOAPP = meso-tetrakis(4-octylamino-phenyl)porphyrinate; M = Y (1), Ho (2)] were prepared as a racemic mixture by treating metal-free phthalocyanine H(2)Pc(alpha-3-OC(5)H(11))(4) with half-sandwich complexes [M(III)(acac)(TOAPP)], generated in situ from M(acac)(3).nH(2)O and H(2)TAPP [TAPP = meso-tetrakis(4-amino-phenyl)porphyrinate], in refluxing 1-octanol. The obtained double-deckers were characterized by elemental analysis and various spectroscopic methods. The molecular structures of 1 and 2 were determined by single-crystal X-ray diffraction analysis. The compounds crystallize in the triclinic system with a pair of enantiomeric double-deckers per unit cell. Resolution of 1 and 2 was achieved using a chiral HPLC technique combined with the formation of their diastereomeric mixture using L-Boc-Phe-OH as the chiral resolving agent, yielding for the first time the pure diastereoisomers of chiral mixed (phthalocyaninato)(porphyrinato) rare earth double-decker complexes with C(4) symmetry. The absolute configuration of these chiral complexes was assigned by comparing the experimental circular dichroism spectrum with a simulated one on the basis of time-dependent density functional theory calculations.

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.