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Nanoscale dynamic processes such as the diffusion of ions within solid-state structures are critical for understanding and tuning material properties in a wide range of areas, such as energy storage and conversion, catalysis, and optoelectronics. In the generation of new types of nanocrystals (NCs), diffusion-mediated ion exchange reactions have also been proposed as one of the most effective transformational strategies. However, retaining the original morphology and crystal structure of metal oxide NCs has been challenging because of Kirkendall void formation, and there has been no success, especially for anion exchange. Here we show that with the aid of an oxygen extracting reagent (OER), anion diffusion is dramatically accelerated and morphology-conserving anion exchange without Kirkendall void formation is possible. In the case of the conversion of Fe

A novel and efficient grafting method for covalent bonding of functional organic molecules to silica or glass surfaces has been developed. The protocol employs transition-metal-catalyzed reactions of vinylsilanes with surface hydroxyl groups. Dimethyldivinylsilane can be used in this procedure as a linker in which one vinyl group is used for direct C-C bond formation with a functional organic molecule and the other is employed to immobilize the alkylsilyl group onto the hydroxyl surface of the solid support.

The intermolecular hydrative dimerization of 1-alkyne was developed through the chelation-assisted catalytic system with Rh(I)/2-amino-3-picoline. This novel transformation afforded branched and linear alpha,beta-enones directly from two 1-alkyne molecules and H2O. The results demonstrate that a branch/linear ratio can be controlled by the alkyl substituent of 1-alkyne.

A new method to separate and reuse the catalyst system consisting of a rhodium complex and 2-aminopyridines for chelation-assisted hydroacylation was achieved using phenol and 4,4'-dipyridyl as the reaction medium, and 4-diphenylphosphinobenzoic acid as a ligand.

The authors have found that directed insertion of a Rh(I) complex into an unstrained carbon-carbon bond, where one of the carbons is a chiral center, provides a new route to rhodium-chiral alkyl complexes. The substrate for C-C activation was (S)-8-quinolinyl ..cap alpha..-methoxybenzyl ketone (..cap alpha..)/sub D/-117/sup 0/. The authors propose that chiral induction at Rh arises from collapse of a tetrahedral intermediate which is on the path to C-C cleavage in these chelating ketones.