Cover Picture: Synthesis of Azepine Derivatives by Rhodium-Catalyzed Tandem 2,3-Rearrangement/Heterocyclization (Angew. Chem. Int. Ed. 43/2012)



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Heterocycle construction through the formation of an azametallacycle from an N-allenylnitrone intermediate is demonstrated in the Communication of I. Nakamura et al. on page 10816 ff. The inherently unstable intermediate can be generated in situ by catalytic 2,3-rearrangement from O-propargylic oximes. This tandem reaction can be compared to a flying trapeze knee hang maneuver.

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Gas Sensors

In their Communication on page 10740 ff., T. M. Swager et al. demonstrate that mechanical abrasion of compressed single-walled carbon nanotubes between metal electrodes on the surface of paper generates sensors that can detect gaseous ammonia at concentrations below 0.5 ppm.

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Pickering Emulsions

In their Communication on page 10746 ff., J. C. M. van Hest et al. describe the stabilization of a Pickering emulsion through fully packed crosslinked polymersomes at the water/oil interface.

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Delivery of siRNA

In their Communication on page 10751 ff., K. Kataoka et al. show that phenylboronate-functionalized micelles can encapsulate siRNAs and then release their cargo in response to a change in ATP concentration.

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