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Herein, the first diversity‐oriented catalytic asymmetric dearomatization of indoles with o‐quinone diimides (o‐QDIs) is reported. The catalytic asymmetric dearomatization (CADA) of indoles is one of the research focuses in terms of the structural and biological importance of dearomatized indole derivatives. Although great achievements have been made in target‐oriented CADA reactions, diversity‐oriented CADA reactions are regarded as more challenging and remain elusive due to the lack of synthons featuring multiple reaction sites and the difficulty in precise control of chemo‐, regio‐, and enantio‐selectivity. In this work, o‐QDIs are employed as a versatile building block, enabling the chemo‐divergent dearomative arylation and [4 + 2] cycloaddition reactions of indoles. Under the catalysis of chiral phosphoric acid and mild conditions, various indolenines, furoindolines/pyrroloindolines, and six‐membered‐ring fused indolines are collectively prepared in good yields with excellent enantioselectivities. This diversity‐oriented synthesis protocol enriches the o‐quinone chemistry and offers new opportunities for CADA reactions. [ABSTRACT FROM AUTHOR]

The first Zn-ProPhenol catalyzed asymmetric inverse-electron-demand Diels–Alder reaction has been accomplished. This protocol was carried out by a dual-activation mode under mild conditions, allowing the preparation of various biologically important dihydropyrans in good yields with excellent stereoselectivities. [ABSTRACT FROM AUTHOR]

A facile chiral phosphoric-acid catalyzed asymmetric inverse-electron-demand aza-Diels–Alder reaction of 1,3-diazadienes with 3-vinylindoles was established. By using this mild and practical protocol, a broad range of benzothiazolopyrimidines with three contiguous stereogenic centers were prepared in good yields and excellent diastereo- and enantio-selectivities (43 examples, up to 83% yield, >99% ee and all >20 : 1 dr). A plausible concerted reaction pathway enabled by the dual hydrogen-bonding effect was proposed to account for the observed excellent enantioselectivity and specific trans–trans diastereoselectivity. [ABSTRACT FROM AUTHOR]

By using a flexible multicarboxylate ligand, 2,2′-(2-((2-carboxy-5-methylphenoxy)methyl)-2-(4-methylphenylsulfonamido)propane-1,3-diyl)bis(oxy)bis(4-methylbenzoic acid) (H 3 L), and two kinds of N-donor ligands, four new zinc(II) and cadmium (II) metal coordination complexes [Zn 2 (HL 2− ) 2 (phen) 2 ]·2H 2 O ( 1 ), [Zn(HL 2− )(4,4′-bpy) 0.5 (H 2 O)] n ( 2 ), [Cd(HL 2− )(phen)(H 2 O)] n ( 3 ), and [Cd 2 (HL 2− ) 2 (4,4′-bpy) 3 ] n ·n(DMF·CH 3 OH·H 2 O) ( 4 ) (phen = 1,10-phenanthroline, and 4,4′-bpy = 4,4′-dipyridine) have been prepared under solvothermal conditions and structurally characterized by elemental analysis, FT-IR spectra, thermogravimetric analysis. The various topologies of the structures have been generated by adjusting the auxiliary N-donor ligand and the central metal ions. Complex 1 features a discrete neutral dinuclear cage structure, complex 2 displays a 1D ladder-like chain, complex 3 exhibits a 1D infinite zigzag chain, while complex 4 possesses a rare 5-connected 2D networks with the point symbol (4 8 ·6 2 ). These results indicate that both the metal center and the auxiliary N-donor ligand have significant influences on the structure of the final assembly. Moreover, the thermal stabilities and luminescent properties of 1 – 4 have also been investigated in detail. [ABSTRACT FROM AUTHOR]

Three complexes with the ditopic ligand 4′-[4-(quinolin-8-yloxymethyl)phenyl]-2,2′:6′,2′′-terpyridine (abbreviated as L), [Ni(L)2](CH3COO)2 ( 1), [Cd(L)2](ClO4)2 ( 2), and [Cu2(L)2](ClO4)4 ·4DMF ( 3), were synthesized and characterized by elemental analysis, IR spectroscopy, and structurally analyzed by X-ray single-crystal diffraction. Interestingly, in complexes 1 and 2, two ligands adopt a tridentate chelating pattern where the oxaquinoline group is non-coordinated and coordinate with one MII ion ( M = Ni for 1, M = Cd for 2) to form a mononuclear unit. In complex 3, two ligands bridge two CuII ions by pyridyl N atoms, ethereal O atoms, and quinolyl N atoms in a head-to-tail mode to generate a dinuclear [Cu2L2] unit. Moreover, extended 1D and 2D supramolecular architectures are further constructed in 1- 3 by multiple secondary interactions such as aromatic stacking and hydrogen bonding. Notably, the structural diversity of complexes 1- 3 can be properly assigned to the central metal ions that have distinct coordination preferences. In addition, luminescent properties of the ligand and complex 2 were also investigated. [ABSTRACT FROM AUTHOR]

A simple quinoline-based fluorescent probe L for Ag + has been developed. Probe L shows fluorescence enhancement (turn on) response towards Ag + with high selectivity in aqueous media (methanol–water, v/v = 3:7, pH 7.2, 20 mM Tris–HCl) based on a combinational effect of the inhibition of intermolecular photoinduced proton transfer and chelation-enhanced fluorescence. And an obvious fluorescent color change could be observed by naked eyes under the light of 365 nm. The binding mode between L and Ag + has been found to be 1:1 based on the fluorescence/absorption titration, ESI-MS and further confirmed by X-ray crystallography. [ABSTRACT FROM AUTHOR]