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Two neodymium β-diketonates metal-organic complexes, Nd(TTA)3TPTZ (1) and Nd(BFA)3TPTZ (2), have been synthesized by using two β-diketone ligands 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione (HTTA) and 4,4,4-trifluoro-1-phenyl-1,3-butanedione (HFBA), and a macrocyclic conjugate ligand, 2,4,6-tri(2-pyridyl)-1,3,5-triazine (TPTZ). The crystal structures of these two complexes were determined by single crystal X-ray diffraction. The X-ray diffraction analysis showed that each neodymium ion in the two complexes formed a Nine-Coordinated structure with six oxygen atoms of HTTA (or HBFA) ligands and three nitrogen atoms of TPTZ ligand by the characteristic of triclinic with P 1 ( — ) space group both. In the crystal structure of the two complexes, a very obvious aromatic donor-acceptor interaction can be observed between adjacent TPTZ ligand molecules, which play an important role in the formation of three-dimensional structures. The complexes were also characterized by infrared spectroscopy, elemental analysis, thermogravimetric and fluorescence spectra. Fluorescence analysis showed that the two complexes exhibited characteristic neodymium-centered emission due to the significant antenna effect of these ligands.

Summary Herein, we describe the protecting-group-free total synthesis of two structurally diverse Isodon diterpenoids, (+)-ent-kauradienone (3) and (−)-jungermannenone C (4), in 12 and 14 steps respectively, through sequential applications of three radical-based reactions, including the photoinduced skeletal rearrangements of bicyclo[3.2.1]octene ring systems. Further investigations of this photochemical radical rearrangement on a series of diverse terpenoids demonstrated both the unparalleled functional-group tolerance and the broad applicability of such late-stage photochemical rearrangements for the synthesis of structurally diverse and complex small molecules. Overall, the mild nature of late-stage photoinduced skeletal rearrangements might suggest that they are possible in a biological setting in unappreciated complimentary biosynthetic pathways.

Two neodymium(III) fluorou ternary complexes, [Nd(C5H2F6O2)3(C18H15OP)2] (C5H2F6O2 = hexafluoroacetylacetone, C18H15OP = triphenylphosphine oxide) (1) and [Nd(C5H2F6O2)3(C12H24N3O4P)2] (C5H2F6O2 = hexafluoroacetylacetone, C12H24N3O4P) = tri(4-morphollno) phosphine oxide) (2) have been synthesized by mild condition. The single crystals suitable for X-ray measurement were obtained and the structures of the two complexes were determined by X-ray diffraction in solid states. Single crystal analysis revealed that the two complexes were both eight-coordinated with one central Nd ion and eight O atoms from ligands. They were crystallized in monoclinic symmetry with P21/c and monoclinic symmetry C2/c space group, respectively. The complexes were characterized by IR-spectroscopy, thermogravimetric, elemental analyses and fluorescent. In fluorescence spectra, the two complexes both exhibit characteristic neodymium-centered emission.

A new sulfenylation reaction has been established, stereoselectively affording 37 examples of α-arylthio-α,β-unsaturated ketones with generally good yields via a metal-free three-component reaction of α-thiocyanate ketones with diaryliodonium salts and 1,2-dicarbonyls. The reaction enabled multiple bond-forming events including C(sp2)–S formation to provide a high-efficient and practical method toward α-arylthio-α,β-unsaturated ketones. The reasonable mechanism for forming α-arylthio-α,β-unsaturated ketones was proposed.

A chiral phosphoric acid-catalyzed Friedel–Crafts alkylation of o -hydroxybenzyl alcohols with 3-alkylindoles has been established, which was used to construct a biologically important diarylindol-2-ylmethane scaffold in high yields and with good enantioselectivities (up to 99% yield, 90:10 er ). Moreover, these novel compounds were subjected to tests to determine the in vitro cytotoxicity against carcinoma Hela cells. Nearly all of the tested compounds exhibited strong or moderate cytotoxicity to Hela cells with IC 50 values ranging from 6.821 to 28.042 μg/mL.

Metal-free (5þ2) cycloadditions of homopyrrole and homofuran with dienophiles of N-phenylmaleimide, dimethyl acetylenedicarboxylate (DMAD), and maleic anhydride have been investigated by DFT calculations at the (U)B3LYP/6-31þG(d) level. Homopyrrole and homofuran act as 4-electron 1,5-dipoles in these (5þ2) reactions. These 1,5-dipoles can exist only in the transition states and undergo competitive concerted or stepwise (5þ2) cycloadditions. The (5þ2) cycloadditions of homopyrrole with dienophiles are stepwise involving generation of diradical intermediates, and its concerted pathways are disfavored marginally. In contrast, the (5þ2) cycloaddition of homofuran with maleic anhydride occurs in a concerted fashion, which is preferred over the stepwise diradical pathway slightly. The distortion energies from homopyrrole and homofuran to their respective 1,5-dipoles in the transition states are not high and this is the main reason why homopyrrole and homofuran can undergo metal-free (5þ2) cycloadditions with dienophiles. 2013 Published by Elsevier Ltd.

One mild multiple emulsions was used for the fabrication of hollow polystyrene (PS) spheres. Polystyrene was dissolved in a volatile organic solvent to form the O phase, then an aqueous phase containing a surfactant was transferred into above phase to form an oil-in-water (W in /O) emulsion, followed by addition of W in /O emulsion in the external W out phase, and solvent evaporation. Final product with diameter of 150 μm, surface roughness of 30 nm, and sphericity of 98.0% was obtained. The possible influences on the formation of PS hollow sphere were also discussed.

Carbon hollow spheres were prepared at temperatures of 400 °C by the reaction reduction of hexachlorobenzene with metallic sodium. Characterized by XRD, TEM, SAED and Raman spectrum to confirm the composition and morphology of the products are confirmed. The possible formation mechanism was also proposed.