Stand and deliver: The first highly regio‐ and enantioselective bromoamination of chalcones has been developed which proceeds via an unusual bromonium‐based mechanism to deliver the title compounds. Excellent results were obtained using 0.05 mol % of the C2‐symmetric N,N′‐dioxide/scandium(III) complex under mild conditions (see scheme).

a Target to triple-shape memory capacity, a series of side-chain liquid crystalline polyurethane networks (SCLCPU-Ns) with well-defined architecture are prepared via an elaborately designed synthetic route: polymerizing the liquid-crystalline (LC) founctionalized monomer with diisocyanate to produce linear polyurethane precursor with uniform distribution of pendant mesogenic units; and then, using tetra-functional pentaerythritol (PTOL) as the crosslinker to produce the PU network with similar backbone length between each crosslinking point. The chemical structures of monomer and linear polyurethane precursor are characterized by nuclear magnetic resonance (NMR). The differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide angle X-ray (WAXD) are employed to verify the nematic nature of liquid crystalline state. DSC analysis combined POM observation reveals that almost all SCLCPU-Ns display two thermal transitions (Tg and Tcl), which can be utilized as Ttrans to trigger the triple shape memory behavior. The cyclic thermomechanical analysis performed by DMA reveals that the networks exhibit excellent triple-shape memory properties, although the architecture of the networks influences their performance. Taking advantage of the overlap of Tg and Tcl in SCLCPU-Ns, which can be regarded as one broad thermal transition, a well-controllable gradual recovering process has been realized in a broad termperature range.

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Catalytic oxidative transformations of alcohols constitute one of the greatly important protocols for the synthesis of various aldehydes, ketones, acids, imines, amides, etc. that are required to make drug intermediates, food additives, plastics, detergents and cosmetics. The potential of gold nanoparticles (Au NPs) in catalytic oxidation reactions is generally competent owing to their tendency to activate oxygen. Supports play a conspicuous and increasingly important role not only in the preparation and stabilization of Au NPs, but also can address the issues of sustainability by facilitating separation and reusability of the catalyst. This review aims to systematically discuss the impressive developments in catalytic oxidative transformations of alcohols promoted by supported Au NPs in the last five years. These Au NPs exhibit unique electronic properties and crystal structures, which gives us an excellent opportunity to correlate atomic structure with intrinsic catalytic properties over Au NPs. The effect of a support on the significant properties of Au NPs in terms of catalytic activity, selectivity, recyclability, and stability is discussed at length. The tentative reaction mechanisms and the structure‐performance relationships are also discussed at appropriate places, which will provide some clues for the design of efficient Au NPs‐based catalysts.

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The chiral hydrogenated tridentate Schiff base-aluminum(III) complex has been first applied in the catalytic enantioselective hydrophosphonylation of trifluoromethyl ketones. The side reactions related to phospha-Brook rearrangement were completely avoided, and the corresponding quaternary α-hydroxy trifluoromethyl phosphonates have been first synthesized in good yields with high enantioselectivities (up to 90% ee).