Article

Pd2L2 metallacycles as molecular containers for small molecules.

MOE Laboratory of Bioinorganic and Synthetic Chemistry, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, 510275, China.
Dalton Transactions (Impact Factor: 4.1). 10/2010; 39(46):11171-9.
Source: PubMed

ABSTRACT M(2)L(2) type metallacyclic complexes, [Pd(2)(L1)(2)Cl(4)]·1.5CH(2)Cl(2) (1), [Pd(2)(L1)(2)Cl(4)]·2CHCl(3) (2), [Pd(2)(L2)(2)Cl(4)]·2CH(2)Cl(2)·2CH(3)CN (3), [Pd(2)(L2)(2)Cl(4)]·2CHCl(3)·2CH(3)CN (4) and [Pd(2)(L3)(2)Cl(4)]·CH(2)Cl(2)·2CH(3)CN (5), have been prepared from three semi-rigid benzimidazol or benzotriazol ligands, 1,4-bis(benzimidazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L1), 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L2) and 1,4-bis(benzotriazol-1-ylmethyl)-2,3,5,6-tetramethylbenzene (L3). All the complexes were structurally characterized by single-crystal X-ray diffraction and the phase purity was confirmed by powder X-ray diffraction (PXRD) measurements. The solution structure of representative complex 1 was studied by (1)H NMR titration and ESI mass spectroscopy. The thermal stability and guest-exchange properties of 1, 3 and 4 were investigated, revealing that the Pd(2)L(2) metallacycles can act as a selective receptor for CH(2)Cl(2) or CHCl(3) guest molecules. The catalytic activity of 1 in Suzuki-Miyaura coupling reaction was also studied and 1 could be recycled at least 5 times under heterogeneous conditions, indicative of a potential self-supported catalyst.

0 Bookmarks
 · 
91 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: A structurally flexible porous metal–organic framework, [CuII(bped)2(H2O)2(SiF6)] ⊃ 4H2O (Cu-MOF-SiF6) was prepared from CuSiF6 and meso-1,2-bis(4-pyridyl)-1,2-ethanediol (bped) in EtOH–H2O. Cu-MOF-SiF6 is a three-dimensional (3D) polycatenated framework consisting of two-dimensional (2D) (4,4) topological grid networks which display 2-fold inclined interpenetration in the crystal lattice. The SiF62− anions hosted in the one-dimensional channels of Cu-MOF-SiF6 can be readily exchanged with NO3− anions while keeping the framework intact, leading to isomorphous Cu-MOF-NO3. The Cu-MOFs show selective adsorption behaviors due to the host–guest interaction, which is dependent on the anions and the guest size. The MeOH uptake investigation indicates that Cu-MOF-SiF6 demonstrates a breathing effect, while Cu-MOF-NO3 exhibits distinctive stepwise MeOH sorption due to the smaller size of NO3− and the larger voids in the crystal lattice. Cu-MOF-NO3 also exhibits stepwise sorption for larger EtOH guests, while the uptake of EtOH is blocked in Cu-MOF-SiF6. In addition, the solids show anion-responsive catalytic properties. Both Cu-MOF-SiF6 and Cu-MOF-NO3 efficiently oxidize benzylic compounds to the corresponding carbonyl functionality under mild and convenient reaction conditions, but improved catalytic activity was observed for Cu-MOF-NO3. The catalysts can be reused with the framework left intact at least three times without losing of any activity.
    Journal of Materials Chemistry 05/2011; 21(20):7098-7104. · 6.63 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Two interlocked trigonal prismatic metalla-cages are formed quantitatively through the self-assembly of π-electron rich arene-Ru acceptors with a new tridentate donor. Interestingly, non-π-electron rich arene-Ru acceptors furnish simple trigonal prisms when they are combined with a tridentate donor.
    Chemical Communications 06/2014; · 6.72 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: New tetranuclear cationic metalla-bowls 5-7 with the general formula [Ru4 (p-cymene)4 (N∩N)2 (OO∩OO)2 ](4+) (N∩N=2,6-bis(N-(4-pyridyl carbamoyl)pyridine, OO∩OO=2,5-dihydroxy-1,4-benzoquinonato (5), OO∩OO=5,8-dioxydo-1,4-naphthaquinonato (6), OO∩OO=hoxonato (7)) were prepared by the reaction of the respective dinuclear ruthenium complexes 2-4 with a bispyridine amide donor ligand 1 in methanol in the presence of AgO3 SCF3 .These new molecular metalla-bowls were fully characterized by analytical techniques including elemental analysis as well as (1) H and (13) C NMR and HR-ESI-MS spectroscopy. The structure of metalla-bowl 6 was determined from X-ray crystal diffraction data. A UV/visible study was also carried out for the entire suite of new complexes. As with recent studies of similar arene-Ru complexes, the inhibition of cell growth by metalla-bowls was established against SK-hep-1 (liver cancer), AGS (gastric cancer), and HCT-15 (colorectal cancer) human cancer cell lines. Inhibition of cell growth by 6 was found to be considerably stronger against all cancer cell lines than the anticancer drugs, doxorubicin and cisplatin. In particular, in colorectal cancer cells, expression of the cancer suppressor genes APC and p53 was increased following exposure to 6.
    ChemBioChem 02/2014; · 3.06 Impact Factor