Polyheterocyclics have been the subject of intense recent research interest.1 Registry No. PP, 30604-81-0; PMT, 84928-92-7.(5) Conductivity values for homogeneous PP films were obtained by using this method and the more conventional four-point method; identical values were obtained. The four-point method cannot be used on these ultranarrow fibers.(6) The surface layers are less than 200 nm thick and cover 100% of the surface area; the fibers are 10 ^m long and occupy 1% (or less) of the surface area.Furthermore, for several membranes, we measured the resistance, scraped off the surface layers, and then remeasured the resistance; Rm values with and without the surface layers were identical.

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A series of polyoxometalates (POMs) that incorporate the highest-nuclearity Ln clusters that have been observed in such structures to date (Ln , Ln=La and Ce) are described, which exhibit giant multishell configurations (Ln⊂W ⊂Ln ⊂W ). Their structures are remarkably different from known giant POMs that feature multiple Ln ions. In particular, the incorporated Ln-O clusters with a nuclearity of 26 are significantly larger than known high-nuclearity (≤10) Ln-O clusters in POM chemistry. Furthermore, they also contain the largest number of La and Ce centers for any POM reported to date and represent a new kind of rare giant POMs with more than 100 W atoms. Interestingly, the La -containing POM can undergo a single-crystal to single-crystal structural transformation in the presence of various transition-metal ions, such as Cu , Co , and Ni , from an inorganic molecular nanocluster into an inorganic-organic hybrid extended framework that is built from POM building blocks with even higher-nuclearity La clusters bridged by transition-metal complexes.

Despite the signficant advances in asymmetric hydrogenation, the development of novel and efficient chiral phosphorus ligands to solve new synthetic challenges continues to an important goal. [1] C 2 -Symmetric chiral bisphosphorus ligands such BINAP, [2] DuPhos, [3] and TangPhos [4] are among the most versatile and important ligands for asymmetric hydrogenation, yet they are not universal. To expand their synthetic utilities, one common strategy is to develop structurally similar ligands, such as Tol-BINAP, Xyl-BINAP, Et-DuPhos, or iPr-DuPhos by increasing the size of the substituents on the phosphorus centers (Figure 1 a). Such modifications lead to the design of ligands with deeper chiral pockets mainly owing to the increased bulk of the R groups, which protrude slightly forward to the substrate coordination. In this study we adopt a new strategy to design a ligand with a deep chiral pocket by installing R groups that protrude directly forward to the substrate coordination site. There are two advantages of this strategy: 1) The R groups that protrude directly forward to the substrate coordination site can lead to a dramatic conformational variation of the chiral pocket; 2) the R groups are in close proximity to the metal center and the substrate, thereby providing a well-defined and deep chiral pocket. We herein report the development of WingPhos (L5) by using this strategy.Chiral b-arylamines exist in numerous biologically interesting natural products and therapeutic agents. For examples, such moieties commonly exist in a series of naphthylisoquinoline alkaloids such as michellamine B and korupensamine A (Scheme 1). [5] They also serve as pivotal structural units for many active pharmaceutical ingredients such as 3,4-methylenedioxyamphetamine (MDA), [6a] tamsulosin, [6b] selegiline, [6c] arformoterol, [6d] rotigotine, [6e] and silodosin. [6f] Development of efficient asymmetric synthetic methods of chiral b-arylamines has thus become a subject of significant interest. [7] However, the asymmetric hydrogenation of b-aryl enamides to prepare chiral b-arylamines remains underdeveloped. Zhang, Lei, and co-workers reported high enantioselectivities on the asymmetric hydrogenation of (Z)-b-aryl enamides by using a Rh-TangPhos catalyst. [8] Nevertheless, low ee values were observed with thermodynamically more stable sub-Figure 1. Design of novel chiral bisphosphorus ligand L5 (WingPhos) with a deep chiral pocket (9-An = 9-anthracenyl). Scheme 1. Selected natural products and therapeutic agents containing chiral b-arylamines.