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Compared to N, O and P as directing functional atoms, the application of directing group containing sulfur atoms for transition metal-catalyzed C-H activation is much more difficult for the known reason (some metal catalysts are easily poisoned by sulfur). Here, the disulfide-directed C-H activation for thew synthesis of sulfonyl diphenyl sulfides was realized for the first time by a copper-catalyzed, tandem, one-step C-S coupling/hydroxylation of disulfides and arylboronic acids with oxygen as the oxidant. This method provides a mild and easy method for the synthesis of sulfonyl diphenyl sulfides and 2-(phenylthio)phenol derivatives and avoids producing sulfoxides and sulfones under air conditions and elevated temperatures. [ABSTRACT FROM AUTHOR]

Abstract: High rate Li3V2(PO4)3/C composite with excellent electrochemical performance has been successfully synthesized via a sample carbon thermal method using meso-tetraphenyl porphyrin (TPP) as carbon source. The as prepared Li3V2(PO4)3/C composite delivers a reversible capacity of 103.71mAhg−1 at 20C charge/discharge rate. The Li+ diffusion coefficient ranges from 10−9 to 10−10 cm2 s−1 based on different scanning rates. The excellent high rate performance may attribute to the small particle size of the LVP/C and the carbon derived from thermal decomposition of TPP. In addition, its application in the full-cell, Li3V2(PO4)3‖Li4Ti5O12, is also presented and discussed. [Copyright &y& Elsevier]

Four simple trans-AB-porphyrins 3a–3d either without any alkoxyl substituent, or with a mono-alkoxyl chain at different (ortho and para) positions of the meso-phenyl ring, or with two alkoxyl chains at two ortho positions of the meso-phenyl ring were designed and synthesized via three steps. The synthesis is simple and no expensive metal catalyst is involved. All compounds were characterized by 1H-NMR and mass spectraometry. UV-Vis absorption spectra and B band-excited fluorescence emission spectra were also obtained. The synthesized porphyrins were applied in dye-sensitized solar cells (DSSCs). Up to 3.05% conversion efficiency was realized for 3d under our experimental conditions, attributed to the two long alkoxyl chains present at the ortho positions of the meso-phenyl group. The influences of the position and the number of the alkoxyl chains at the macrocyclic meso-phenyl group on the photovoltaic performance of DSSCs are well explained via DFT calculations. It was shown that the VOC and JSC of the sensitizers are determined by μnormal, ΔGinject and LHE. [ABSTRACT FROM AUTHOR]

The title composite is prepared from mixtures of V2O5, Li2CO3, NH4H2PO4, and meso-tetraphenyl porphyrin as the carbon source (350 °C for 4 h followed by sintering at 800 °C for 8 h in N2 atmosphere). [ABSTRACT FROM AUTHOR]