Structural transformations from a 1-D chain to two 3-D supramolecular isomers via crystal disassembly and reassembly

The reaction of L(-)-malic acid (L-H(2)mal), manganese salts and triethylamine in methanol - water solution gave a 1-D chiral complex, [Mn-II(L-mal)(H2O)(CH3OH)] 2 (1), which could be rationally controlled to transform into 3-D supramolecular isomers [Mn-II(L-mal)(H2O)(2)] center dot H2O (2a and 2b, respectively)

Ferromagnetic interactions in a bis(mu-end-on azido)cobalt(II) linear trimer

通讯作者地址: Tao, J (通讯作者), Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Zhangzhou Inst Technol, Dept Food & Bioengn, Zhangzhou, Fujian Peoples R ChinaA linear trinuclear Co(II) compound, [Co-3(mu(1,1)-N-3)(4)(N-3)(2)(H2O)(2)(bpbp)(2)] center dot 2H(2)O (1, bpbp = 3,3'-bis-Dimethytamino-1,1'-pyridine-2,6-diyl-bispropenone), is reported. The central Co(II) ion is bridged to Co(II) ions on both sides by four end-on azide (mu(1,1)-N-3(-)) ligands resulting in a centrosymmetric trimer with adjacent Co center dot center dot center dot Co distance of 3.233 angstrom. Each Co(II) ion possesses distorted octahedral geometry, the central one is coordinated by two aqua ligands and four mu(1,1)-N-3(-) nitrogen atoms and each terminal Co(II) is coordinated by two mu(1,1)-N-3(-) nitrogen atoms, one terminal N-3(-) nitrogen atom and capped by terminal tridentate bpbp ligand. Variable temperature magnetic studies indicate ferromagnetic coupling between adjacent Co(II) ions within the trimer. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved

Ferromagnetic interactions in a bis(mu-end-on azido)cobalt(II) linear trimer

通讯作者地址: Tao, J (通讯作者), Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Zhangzhou Inst Technol, Dept Food & Bioengn, Zhangzhou, Fujian Peoples R ChinaA linear trinuclear Co(II) compound, [Co-3(mu(1,1)-N-3)(4)(N-3)(2)(H2O)(2)(bpbp)(2)] center dot 2H(2)O (1, bpbp = 3,3'-bis-Dimethytamino-1,1'-pyridine-2,6-diyl-bispropenone), is reported. The central Co(II) ion is bridged to Co(II) ions on both sides by four end-on azide (mu(1,1)-N-3(-)) ligands resulting in a centrosymmetric trimer with adjacent Co center dot center dot center dot Co distance of 3.233 angstrom. Each Co(II) ion possesses distorted octahedral geometry, the central one is coordinated by two aqua ligands and four mu(1,1)-N-3(-) nitrogen atoms and each terminal Co(II) is coordinated by two mu(1,1)-N-3(-) nitrogen atoms, one terminal N-3(-) nitrogen atom and capped by terminal tridentate bpbp ligand. Variable temperature magnetic studies indicate ferromagnetic coupling between adjacent Co(II) ions within the trimer. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved

Magnetic Nanosized {M-24(II)}-Wheel-Based (M = Co, Ni) Coordination Polymers

通讯作者地址: Tao, J (通讯作者),Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China 2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China 电子邮件地址: [email protected] 3D coordination polymers, [Co-24(OH)(12)(SO4)(12)(ip)(6)(DMSO)(18)(H2O)(6)]center dot(DMSO)(6)-(EtOH)(6)(H2O)(36) (1.guests, ip = isophthalate) and [Ni-24(OH)(12)(SO4)(12)(ip)(6)(DMSO)(12)(H2O)(12)]center dot(DMSO)(6)-(EtOH)(6)(H2O)(20) (2.guests), constructed with nanosized tetraicosanuclear Co-II and Ni-II wheels are solvothermally synthesized. Both complexes show intra- and interwheel dominant antiferromagnetic interactions.NNSF of China 90922012 20971106 21021061 Specialized Research Fund for the Doctoral Program of Higher Education 2011012111001

Synthesis, crystal structure and magnetic properties of a mixed-valence pentanuclear cobalt complex

Solvothermal reaction of Co(OAc)(2)center dot 4H(2)O with H4L (H = 2-((2-hydroxybenzylidene)amino)-2-hydroxymethylpropane-1,3-diol) in MeCN gave a mixed-valence pentanuclear cobalt complex [Co-5(HL)(2)(H2L)(2)(OAc)(2)]center dot 2.5H(2)O. Crystal structural analysis revealed that two Co(III) ions were linked to a central triangular Co(II) core through HL3- and H2L2- hydroxyl groups. Magnetic measurements showed interesting magnetic properties that were assigned to spin-orbital coupling and ferromagnetic exchange interactions.NNSF of China [20671079, 20721001]; Chinese Ministry of Education [107068]; NECTFJ ; MSTC [2007CB815301

Temperature, light and solvent-induced spin transition in a 3D 2-fold interpenetrated PtS-type porous coordination polymer

A 3D 2- fold interpenetrated porous coordination polymer, [Fe(NCS)(2)( tppm)]center dot 5CH3OH center dot 2CH2Cl2 (1 center dot sol, tppm = 4,4',40'',4''- tetrakis(4- pyridylethen- 2- yl) tetraphenylmethane), was synthesized, which showed temperature, light and solvent- induced spin- crossover behaviours

Metal-organic frameworks displaying single crystal-to-single crystal transformation through postsynthetic uptake of metal clusters

NNSF of China [21021061, 20923004]; Specialized Research Fund for the Doctoral Program of Higher Education [2011012 1110012]Three metal-organic frameworks(MOFs) formulated as [Co3O(BTB)(2)(H2O)x(DMF)(y)]center dot zDMF center dot nH(2)O(BTB 1,3,5-benzenetribenzoate; 1a, x = y = 1, z = 7.5, n = 12; 1b, x = 2, y = 0, z = 8.5, n = 8; 1c, x = 2, y = 1, z = 7, n = 8) have been synthesized under different temperatures; they crystallize as two-fold interpenetrated analogous structures with the same structural trinuclear Co3O(CO2)(6) secondary building units (SBUs), and their stabilities depend on the temperature under which they formed. Upon immersion in the filtrate of 1a (namely 1a-s, freshly filtered) or 1b (namely 1b-s, filtered and then activated in air for three days), single crystal-to-single crystal (SCSC) transformations of 1a-1c to a new MOF, formulated as [Co6O2(OH)4(BTB)(8/3)(H2O)(4)]center dot 14DMF center dot 4EtOH center dot 2H(2)O (2), occur along with dramatic color change from blue purple to red. Crystallographic studies reveal that the new MOF is also two-fold interpenetrated but is constructed with hexanuclear Co6O2(CO2)(8) SBUs. This SCSC transformation from 1a-1c to 2 can take place only in 1a-s or 1b-s but not in 1c-s and is accompanied with an increase of metal-to-ligand ratio. ESI-MS studies unveil the formation of free {Co3O} units in situ formed only in 1a-s and 1b-s, and evidence that the SCSC transformation involves a postsynthetic uptake of free metal clusters, {Co3O}. On the other hand, the SCSC transformation speed decreases from 1a to 1c, which is determined by the chelate carboxylate groups undergoing cleavage of metal-carboxylate bonds during the SCSC transformation and the shape of the 1D channels affecting the diffusion of free metal clusters. Furthermore, the resulting MOF (2) can maintain its crystallinity upon activation and adsorbs iodine up to 38 wt%. Combined with the significant SCSC transformation through postsynthetic uptake of free metal clusters and the resulting MOF capable of adsorbing iodine, the present approach not only provides a true route to construct SBUs-based MOF materials with pre-existing "real" SBUs but also represent a new type of SCSC transformation in the field of MOFs that is able to efficiently tune structures and physicochemical properties of MOFs in the solid states

Side-effect of ancillary ligand on electron transfer and photodynamics of a dinuclear valence tautomeric complex

A cobalt complex [{Co(dpqa)}(2)(dhbq)](PF6)(3) (1(PF6)(3), dhbq = deprotonated 2,5-dihydroxy-1,4-benzoquinone, dpqa = di(2-pyridylmethyl)N-(quinolin-2-ylmethyl) amine) was prepared and studied by X-ray diffraction, electrochemistry, ESR, thermally and photo-induced magnetic measurements; the results show that the ancillary ligand finely tuned structural factors as well as intermolecular interactions that affect the VT behavior

A boracite metal-organic framework displaying selective gas sorption and guest-dependent spin-crossover behaviour

NNSF of China [21021061, 20923004]; Specialized Research Fund for the Doctoral Program of Higher Education [20110121110012]A metal-organic framework, [{Fe(NCS)(2)}(3)(TPB)(4)]center dot x(guest) [1 center dot x(guest), TPB = 1,3,5-tris(4-pyridyl)benzene], shows selective gas adsorption and guest-dependent spin-crossover behaviour

The effects of pressure on valence tautomeric transitions of dinuclear cobalt complexes

The effects of pressure on valence trautomeric transition behavior of two complexes, [{Co(tpa)}(2)(dhbq)]center dot(PF6)(3) (I center dot(PF6)(3)) and [{Co(dpqa)}(2)(dhbq)]center dot(PF6)(3) (II center dot(PF6)(3)) (tpa= tris(2-pyridylmethyl)-amine, dpqa = di(2-pyridylmethyl)-N-(quinolin-2-ylmethyl)-amine and dhbq = deprotonated 2,5-dihydroxy-1,4-benzoquinone), in the light of changes of magnetic susceptibilities were investigated; the results show that external pressure makes the SC + ET transition process of the two complexes into a general SC process only.NNSF of China [20671079, 20721001]; Key Project of Chinese MOE [107068]; NECTFJ ; MSTC [2007CB815301