An iron-containing POM-based hybrid compound as a heterogeneous catalyst for one-step hydroxylation of benzene to phenol.

It is a major challenge to perform one-pot hydroxylation of benzene to phenol under mild conditions, which replaces the environmentally harmful cumene method. Thus, finding highly efficient heterogeneous catalysts that can be recycled is extremely significant. Herein, a (POM)-based hybrid compound {[FeII(pyim)2(C2H5O)][FeII(pyim)2(H2O)][PMoV2MoVI9VIV3O42]}·H2O (pyim = 2-(2-pyridyl)benzimidazole) (Fe2-PMo11V3) was successfully prepared by hydrothermal synthesis using typical Keggin POMs, iron ions and pyim ligands. Single-crystal diffraction shows that the Fe-pyim unit in Fe2-PMo11V3 forms a stable double-supported skeleton by Fe-O bonding to the polyacid anion. Remarkably, due to the introduction of vanadium, Fe2-PMo11V3 forms a divanadium-capped conformation. Benzene oxidation experiments indicated that Fe2-PMo11V3 can catalyze the benzene hydroxylation reaction to phenol in a mixed solution of acetonitrile and acetic acid containing H2O2 at 60 °C, affording a phenol yield of about 16.2% and a selectivity of about 94%.

MoO42--templated Ln20Ni21 heterometallic clusters with large low-field magnetic entropy.

The anionic template method is an effective strategy for synthesizing high-nuclearity transition-lanthanide (3d-4f) heterometallic clusters. Herein, two lanthanide clusters with formulas [Gd20Ni21(µ3-OH)21(CO3)6(IDA)21(C2H4NO2)6(C2O4)3(MoO4)1.5(µ2-OH)1.5(H2O)9]Cl10.5·79H2O (1) and [Tb20Ni21(µ3-OH)21(CO3)6(IDA)21(C2H4NO2)6(C2O4)3(MoO4)(µ2-OH)2(H2O)10]Cl11·32H2O (2) were synthesized by introducing MoO42- anions as templates. Structural analysis indicates that compounds 1 and 2 are isomorphic, featuring a fascinating triangular-shaped metal framework. Magnetic property investigations illuminate the fact that compound 1 exhibits a large -ΔSm of 37.83 J kg-1 K-1 at 3 K for ΔH = 7 T. In particular, it is worth mentioning that compound 1 has an excellent low-field magnetic entropy (-ΔSm = 23.85 J kg-1 K-1 at 2 K, 2 T).

Two bimetal-doped (Fe/Co, Mn) polyoxometalate-based hybrid compounds for visible-light-driven CO2 reduction.

Two polyoxometalate (POM)-based hybrid compounds have been successfully designed and constructed by the hydrothermal method with molecular formulas [K(H2O)2FeII0.33Co0.67(H2O)2(DAPSC)]2{[FeII0.33Co0.67(H2O)(DAPSC)]2[FeII0.33Co0.67(H2O)4]2[Na2FeIII4P4W32O120]}·21.5H2O (1), and [Na(H2O)2FeII0.33Mn0.67(H2O)2(DAPSC)]2{[FeII0.33Mn0.67(H2O)(DAPSC)]2[FeII0.33Mn0.67(H2O)4]2[Na2FeIII4P4W32O120(H2O)2]}·24H2O (2) (DAPSC = 2,6-diacetylpyridine bis-(semicarbazone)), respectively. Structural analysis revealed that 1 and 2 consisted of metal-organic complexes containing DAPSC ligands with dumbbell-type inorganic clusters, iron-cobalt (iron-manganese) and some other ions. By utilizing a combination of strongly reducing {P2W12} units and bimetal-doped centres the CO2 photoreduction catalytic capacity of 1 and 2 was improved. Notably, the photocatalytic performance of 1 was much better than that of 2. In CO2 photoreduction, 1 exhibited CO selectivity as high as 90.8%. Furthermore, for 1, the CO generation rate reached 6885.1 µmol g-1 h-1 at 8 h with 3 mg, and its better photocatalytic performance was presumably due to the introduction of cobalt and iron elements to give 1 a more appropriate energy band structure. Further recycling experiments indicated that 1 was a highly efficient CO2 photoreduction catalyst, which could still possess catalytic activity after several cycles.

Layered Co-O Cluster Applied to Photocatalytic CO2 Reduction.

In the field of recycling CO2, the photocatalytic CO2 reduction reaction (CO2RR) is a typical example, and researchers have designed a variety of photocatalysts to improve the conversion rate of CO2 over the years. In this paper, two metal-oxygen clusters are designed and formulated as [Co3Zn(OH)6(SO4)]·4H2O (1) and [Ni3Zn(OH)6(SO4)]·4H2O (2). As for compound 1, the main structure is composed of {CoO6} octahedra connected by edge-sharing to form a two-dimensional layer, on which {ZnO4} and {SO4} tetrahedra are supported. More interestingly, compound 1 has outstanding photocatalytic activity, which is mainly attributed to the open-framework structure and the cobalt ions as active sites. Upon catalysis for eight hours, its maximum CO generation rate is 9982.13 µmol g-1 h-1, with a selectivity of 81.8%. Additionally, compound 1 takes on weak antiferromagnetic coupling due to Co(II) ions.

[GPI-PLD gene exon14 polymorphisms of leucocyte in peripheral blood from healthy persons and leukemia patients].

OBJECTIVE: To analyze the polymorphisms of glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) gene exon 14, GPI-PLD activity of leucocyte in the peripheral blood,and the relationship in leukemia patients of Han nationality in Hunan. METHODS: Both 96 leukemia patients and 96 healthy persons of Han nationality in Hunan were researched [including 48 acute non-lymphocytic leukaemia (ANLL) patients as group A, 31 acute lymphoblastic leukaemia (ALL) patients as group B, 12 chronic granulocytic leukaemia (CML) patients as group C, 5 chronic lymphocytic leukaemia (CLL) patients as group D]. The polymorphisms were analyzed by PCR-SSCP and sequencing;. and GPI-PLD activities were determined by GPI-anchored placental alkaline phosphatase (PLAP) as substrate and triton-X114 partioning. RESULTS: There were four variations in the coverage of GPI-PLD gene exon 14 of leukemia patients and healthy persons. The codons of variation were: 1257 C-->T, 1298 T-->C, 1218 C-->A, 1257 C-->A. The total various frequency in leukemia patient and healthy person, which was determined by SSCP, was 28.12% and 20.83%. On the basis of the percentage of GPI-anchored PLAP conversion, the leucocyte GPI-PLD activities of the 96 leukemia patients were measured. Compared with the 96 healthy controls, the leukocyte GPI-PLD activites of ANLL and CLL patients were significantly increased; the acticities of ALL and CML patients were significantly reduced. CONCLUSION: Leukocyte GPI-PLD gene in the peripheral blood, which belongs to healthy persons and leukemia patients of Han nationality in Hunan, is polymorphism. The leukocyte GPI-PLD activities in the four groups are remarkable.

[Effect of the expression of glycosylphosphatidylinositol-specific phospholipase D gene on K562 cell sensitivity to complement killing].

OBJECTIVE: To detect the release of glycosylphosphatidylinositol (GPI) anchored CD55 and CD59, and the effect of complement dependent cytotoxicity on K562 cell with expression of GPI-PLD by glucose or insulin. METHODS: CD55 and CD59 were detected by Western blotting; GPI-PLD activities were analyzed quantitatively; and complement dependent cytotoxicity (CDC) effects were observed by staining of trypan blue. RESULTS: After being induced by insulin or glucose for 24 h and 48 h, GPI-PLD activities and rate of CDC killing in the insulin, insulin + glucose groups significantly increased. At 24 h after the inducement, CD55 was found in the membrane proteins in the control, glucose and insulin groups and CD59 in membrane proteins in the control, glucose group, and medium supernatants of insulin, glucose + insulin groups. Both CD55 and CD59 were found in membrane proteins in control group, and medium supernatants of glucose, insulin, glucose + insulin group at 48 h after the inducement. CONCLUSION: Treatment with insulin resulted in the obvious increase of GPI-PLD activity in K562 cell, which led to releasing of GPI anchored CD55 and CD59 into medium, and increased sensitivity of these cells to CDC killing.