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The hydrolysis of a phosphanorbornenium triflate to obtain the expected tertiary phosphine oxide by cleavage of one P-C bond of the bridge in the presence of triethylamine is reported. The secondary phosphine oxide by cleavage of the two P-C bonds of the bridge in the presence of [alpha]-picoline is also reported.

Carbon nanotubes (CNTs) and other related CNT-based materials with a high thermal conductivity can be used as promising heat dissipation materials. Meanwhile, the miniaturization and high functionality of portable electronics, such as laptops and mobile phones, are achieved at the cost of overheating the high power-density components. The heat removal for hot spots occurring in a relatively narrow space requires simple and effective cooling methods. Here, an auxiliary passive cooling approach by the aid of a flat plate (aluminum–magnesium alloy) is investigated to accommodate heat dissipation in a narrow space. The cooling efficiency can be raised to 43.5%. The cooling performance of several CNT-based samples is compared under such circumstances. Heat dissipation analyses show that, when there is a nearby plate for cooling assistance, the heat radiation is weakened and natural convection is largely improved. Thus, improving heat radiation by increasing emissivity without reducing natural convection can effectively enhance the cooling performance. Moreover, the decoration of an auxiliary cooling plate with sprayed CNTs can further improve the cooling performance of the entire setup. [ABSTRACT FROM AUTHOR]

The one-pot, palladium-catalyzed, three-component coupling of aryl bromides, internal alkynes, and environmentally friendly K4Fe(CN)6provides an efficient and direct method for the preparation of -arylalkenylnitriles. [ABSTRACT FROM AUTHOR]

The reaction of a phosphole-2,5-diol with a tripyrromethane in the presence of BF3generates, after oxidation by DDQ, a P-confused carbaporphyrinoid whose X-ray crystal structure analysis has been performed. The steric bulk of the phosphorus subunit prevents the formation of the expected phosphaporphyrin. [ABSTRACT FROM AUTHOR]

In contrast with an earlier report, the reaction of 1-phenyl-3,4-dimethylphosphole with an excess of dimethyl acetylenedicarboxylate (DMAD) at room temperature affords the phosphole + 2 DMAD ylide 10, whose structure was established by a careful analysis of the 13C NMR spectrum. Its stability is surprising, since the analogous Ph 3P + 2 DMAD adduct spontaneously rearranges to other products and has never been fully characterized. When the reaction of phosphole with DMAD was carried out in the presence of AgNO 3, the intermediate 1:1 adduct was oxidized to the stable oxo-ylide 13, whose X-ray crystal structure shows the highly zwitterionic character. [ABSTRACT FROM AUTHOR]