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Two novel limonoids, chuktabrin A ( 1), featuring the unique motifs of a 1,3-dioxolan-2-one and a 3,4-dihydro-2 H-pyran, and chuktabrin B ( 2), possessing an unprecedented polycyclic skeleton, were isolated from Chukrasia tabularis. The structures of 1and 2bearing a biosynthetically extended C3 and C2 unit at C-15, respectively, were elucidated on the basis of spectroscopic data, and that of 1was confirmed by a single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

A heterocycle containing phosphorus, known as dialkyl‐2H‐1,2‐phosphasiliren‐3‐olate 2, is synthesized through the reaction of dialkylsilylene 1 and sodium phosphaethynolate (NaOCP) in a high yield at ambient conditions. The structure of 2 is determined by single‐crystal X‐ray diffraction and multinuclear NMR spectroscopy. The theoretical studies are identified two nucleophilic centres located on the phosphorus (P) and oxygen (O) atoms, respectively. According to WBIs and the crystal characterization analyses, both the C−P and C−O bonds in the C−Si‐P three‐membered ring have significant double bond character. Reactions involving R3SiCl and Me2SO4 with 2 at room temperature are also conducted at room temperature. The nucleophilic substitution reaction can also occur on oxygen atom of 2, and yield ring‐retaining products 3 and 4 a–4 c, respectively. When acyl chlorides are employed as electrophiles, the derivatives of (silylmethylidyne)phosphane, 6 a–6 c, are produced as a result of the substitution of the oxygen atom. [ABSTRACT FROM AUTHOR]

Abstract: A novel D-A compound, [Cu(L)2Cl2]·2CH2Cl2 ML, has been synthesized based on 4′,5′-diaza-9′-(4,5-bis(benzylthio)-1,3-dithiole-2-ylidene)-fluorene ((C11N2H6)(C3S2)(SCH2C6H5)2, L). Both ML and L are further characterized by elemental analysis, IR, 1H and 13C NMR. Single-crystal X-ray diffraction shows ML displays a 3-D supramolecular network built by the neutral mononuclear unit [Cu(L)2Cl2] via hydrogen bonds, π–π stacking and S⋯S interactions. The UV–Vis spectra show the lowest-energy absorption band (431nm) of ML is red-shifted compared to that of L (415nm). The electrochemistry behavior shows that while the HOMO level of the ML is lowered by L coordinating with the Cu2+ ion, the oxidative potentials are increased (1.19 to 1.37V). Photocurrent measurements show the intramolecular charge transfer (ICT) of L should be easier than that of ML. The results of the reorganization energy obtained from DFT calculations (λ i: 0.25eV for L, 0.82eV for ML) reveal the lower reorganization energy is of great benefit to carrier transport within L. These results are in good agreement with those experimentally obtained by CV, UV–Vis, fluorescence and photocurrent measurements. [Copyright &y& Elsevier]

A novel three-dimensional barium metal-organic framework [Ba3(btc)2(H2O) 4 ]·0.5H2O (H3btc = 1,3,5-benzenetricarboxylic acid) has been synthesised under hydrothermal conditions, and characterised by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, IR, and photoluminescence studies. The volume of the tunnel formed by the two-dimensional layers is 341.9 Å3 per unit cell using PLATON based on the crystal structures, comprising 14.3% of the crystal volume 2387.2 Å3. The solid-state fluorescence measurement of this compound at room temperature reveals a fluorescent emission band at 454.5 nm under the excitation of 337 nm, assigned to a charge-transfer transition. [ABSTRACT FROM AUTHOR]

A new Zn(II) phosphonate, (NH4)[Zn(HPMIDA)(H2O)2] (1) (H4PMIDA = N-(phosphonomethyl)iminodiacetic acid), has been solvothermally synthesized and characterized by elemental analysis, IR, TGA fluorescence, and X-ray single-crystal diffraction. Compound 1 is an example of a six-coordinate Zn-carboxylate-phosphonate and possesses a 3-D supramolecular structure built from mononuclear anions [image omitted] through hydrogen bonding. Compound 1 exhibits a solid-state fluorescent emission band at 593 nm under excitation of 413 nm. [ABSTRACT FROM AUTHOR]

CuI is used to control the molecular orientation of copper phthalocyanine (CuPc) and modify the anodes in organic solar cells based on CuPc/C60. By introducing a CuI buffer between indium tin oxide and CuPc, the power conversion efficiency is significantly enhanced by a factor of ∼70%. Because of the strong interactions between the CuI and CuPc, the stacking orientation of CuPc molecules is changed, resulting in a ∼65% increase in absorption coefficient, a larger carrier mobility and a smoother film surface. The anode work function is raised by the formation of a dipole layer. [ABSTRACT FROM AUTHOR]