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Complexes of a poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized by hydrogen bonds were prepared. By introducing poly(ethylene glycol), the complexes possessed shape memory effect, due to which a large difference in storage modulus below and above the glass transition temperature occurred. The morphology of the complexes was investigated and the mechanism of the shape memory behavior was discussed. This kind of complexes can be regarded as a novel shape memory network.

Optically active tertiary aminonaphthol 1 was obtained by a new, convenient procedure and was found to catalyze the enantioselective alkenylation of various aldehydes with high ee values, which provides a practical method for the synthesis of chiral (E)- allyl alcohols.

Dedicated to Joe P. Richmond on the occasion of his 60 th birthday.Abstract: A one-pot, titanium-catalyzed tandem sulfoxidation-kinetic resolution process, which combines asymmetric oxidation (at lower temperature) and kinetic resolution (at room temperature), has been developed. Excellent ees (up to > 99.9%) and higher chemical yields of sulfoxides were obtained and the results compared favorable with those from either oxidation or kinetic resolution.

A new chiral tertiary aminonaphthol ligand 3b served as a highly efficient ligand for the asymmetric catalytic phenyl transfer to aromatic aldehydes and a variety of chiral diarylmethanols was prepared in high ee values (ee up to 99%) and chemical yields. The straightforward syntheses of both 3b and its enantiomer provide an excellent opportunity for large-scale applications.

The epoxidation of cyclic alkenes with molecular oxygen was efficiently completed in excellent epoxide yield using a novel ruthenium complex as catalyst under mild reaction conditions.

Air-and water-stable fluorinated ferrocenylphosphine-aminophosphine ligands have been synthesized and applied to the Rh-catalyzed asymmetric hydrogenation of enamides and a-dehydroamino acid derivatives. These reactions afforded the corresponding products in good to excellent ees (up to 99.7% ee) and nearly quantitative yields. The combination of the remarkable air-and waterstability with excellent catalytic performance makes these catalysts excellent choices for practical applications.Keywords: air-stable ligands; asymmetric hydrogenation; enamides; ferrocenylphosphine-aminophosphine ligands; rhodium Asymmetric catalytic reactions have attracted much attention in recent years because of their great potential in making higher-value-added products. [1] In this respect, the use of chiral ligands has played a very important role.[2] So far many chiral ligands have been prepared and used for Rh-and Ru-catalyzed asymmetric hydrogenation.[3] Although moderate to excellent enantioselectivities have been achieved using these ligands, most of the catalytic reactions needed to be performed with the strict exclusion of oxygen and moisture, thus making them quite inconvenient for general organic synthesis and industrial applications. From a practical standpoint, it is desirable to develop effective, easily prepared chiral ligands and catalysts with high air-and water-stability, so that the associated catalytic reactions can be easily carried out in ordinary laboratory or industrial settings.Chiral ligands with a ferrocenyl backbone have found useful applications in transition metal-catalyzed asymmetric hydrogenations. [1,3,4] Some well known examples include Hayashis (aminoalkyl)ferrocenylphosphine ligands, [5] Tognis Josiphos-type ligands, [6] Burks Ferro-TANE-type ligands, [7] Knochels ferrocenyl ligands with two phosphanyl substituents, [8] Zhangs f-binaphane [9] and Spindlers Walphos-type ligands.[10] Recently, Baoz et al. reported the preparation of phosphinoferrocenylaminophosphines and their application in the rhodium-catalyzed asymmetric hydrogenation with high activities and enantioselectivities.[11] In our quest for highly efficient ligands in asymmetric hydrogenation, [12] we became interested in ferrocene-based ligands with high efficiency and stability. Herein we report the interesting findings of some new fluorinated phosphinoferrocenylaminophosphines in rhodium-catalyzed asymmetric hydrogenation. The distinctly high air-and water-stabilities of the fluorinated ligands as well as their Rh(I) complexes, combined with the high enantioselectivities in asymmetric hydrogenation, make them good choices for practical applications.We first examined ligand 1 (Scheme 1) in hydrogenation of arylenamides, and relatively poor ee values were observed in contrast to the results obtained from the hydrogenation of a-dehydroamino acid derivatives under similar conditions ( > 99% ee).[11] This is not surprising because chiral ligands for asymmetric catalysis usually perform well for specific types of substrates. It is w...