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Intermolecular fluorocyclization of indoles with anthranilates, which proceeded smoothly to give diverse indoloquinazolinone architectures under mild reaction conditions, has been developed. A wide range of substrates were compatible with this cyclization system. The synthetic fluorinated compounds could be modified by their conversion to various substituted quinazolinones for drug discovery. In addition, this protocol has been applied to the concise total synthesis of bioactive natural alkaloids phaitanthrins A–B, cephalanthrin A and cruciferane. [ABSTRACT FROM AUTHOR]

To strengthen the adhesion of platinum layer to counterelectrodes of dye sensitized solar cells, titanium thin film has been utilized as adhesion layer between platinum and substrate [Wei et al., Appl. Phys. Lett. 90, 153122 (2007)]. In our study, platinum/titanium bilayer counterelectrodes were fabricated by magnetron sputtering. The structural, electrical, and electrochemical properties of the bilayer counterelectrode were studied by varying the thickness of both platinum and titanium layers. The influence of both electrochemical active surface and crystallite size on charge transfer resistance of the bilayer counterelectrode was explored. From these evaluations, it was found that the as-prepared titanium layer was almost amorphous, and intermetallic phase was formed between platinum and titanium layers. As expected, sheet resistance of the electrode decreased with the increase in deposition time of both platinum and titanium layers. Metal titanium was found to be inert in the catalyzing reduction in tri-iodide. With the increment of deposition time of platinum layers, charge transfer resistance of the electrode decreased quickly first, and then reached a plateau after which it changed slightly. This outcome differs from that reported before. Careful examination showed that such a behavior was related closely to the electrochemical active surface area of electrode and platinum crystallite size. For a given electrolyte, charge transfer resistance decreased with the increase in electrochemical active surface and increased with the increment of the latter. Thus, a competition was observed between the two factors, which supports the suggestion of former researchers. [ABSTRACT FROM AUTHOR]

An organocatalytic, highly facile, efficient, and regioselective ortho-chlorination of anilines is described. A secondary ammonium chloride salt has been employed as the catalyst and the reaction can be conducted at room temperature without protection from air and moisture. In addition, the reaction is readily scalable and the catalyst can be recycled and reused. This catalytic protocol has been applied to the efficient synthesis of a highly potent c-Met kinase inhibitor. Mechanistic studies revealed that unique structural features of the secondary ammonium chloride salt are important for both the catalysis and regioselectivity of the electrophilic ortho-chlorination. [ABSTRACT FROM AUTHOR]

Novel sulfur and selenium-bridged [8]circulenes were prepared from octabromotetraphenylene. Structures of these compounds were unambiguously confirmed by X-ray crystallographic analyses. Photophysical and electrochemical investigations of these [8]circulenes suggest their potential applications as electronic materials. The antiaromatic nature of tetrathio[8]circulene and tetraselenium[8]circulene was studied by computational methods, and the NICS computational results reveal that the central eight-membered ring has highly antiaromatic character. [ABSTRACT FROM AUTHOR]

As the elevation information is not considered in the traditional building change detection methods, this paper presents an algorithm of combining LiDAR data and aerial imagery for the 3D building change detection. With the proposed method, we can extract both the elevation change information and the area change information of the buildings at the same time. Firstly, two DSMs are generated using two periods of LiDAR data. Secondly, differencing, filtering and morphological operations are performed to get the changed DSM area, which is then projected onto the aerial images according to the collinearity equations. After that, the interference of the pseudo-changing areas such as trees is removed using spectrum and texture information of aerial image. Finally, the value of elevation changes and area changes are calculated. Experimental results show that the proposed algorithm can extract the change information of the elevation and area quantitatively, which can provide more comprehensive and accurate information for the building change detection. [ABSTRACT FROM AUTHOR]

In this paper, a new relative orientation algorithm based on intersecting lines is proposed. Relative orientation parameters are obtained with the intersection equations of the extracted corresponding intersecting lines. The algorithm needs no corresponding points and can be used to solve the problem of relative orientation lacking corresponding points. Experiments with aerial images, close-range images, and oblique images show that the proposed algorithm can gel robust results. Relative orientation results are more accurate and robust when combining the proposed algorithm and the traditional relative orientation method using corresponding points. [ABSTRACT FROM AUTHOR]