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Carbazole is an important compound in pharmaceuticals and functional materials. A new Pd(II) supramolecular cage-catalyzed protocol for the synthesis of multifunctional carbazoles from indoles is described through regioselective successive oxidative Heck reactions. This new protocol is highly efficient, with a low Pd (2.4 mol%) catalyst loading and good compatibility for both N-H free and N-protected indole substrates. Moreover, it can be used to synthesize carbazoles with various functional groups by a one-pot two-step procedure. The excellent catalytic activity can be attributed to the distinct properties of the supramolecular cage structure in uniformly distributive and well-defined Pd(II) active centers on the cage surfaces.

A series of porous MOFs with hendecahedron cage-liked cavity has been constructed from the [Cu2(COO)4] secondary building unit, H3L (H3L = [1,1';3',1'']Terphenyl-4,5',4''-tricarboxylic acid) and pyrazine derivatives varied with different sizes; the structural evolving of the hendecahedron cage and the application in drug delivery and controlled release were presented.

C36H48CoN2O28S2, monoclinic, P21/c (no. 14), a = 18.2239(13) Å, b = 7.1282(6) Å, c = 17.8550(13) Å, β = 97.883(2)°, V = 2297.5(3) Å3, Z = 2, R gt(F) = 0.0906, wR ref(F 2) = 0.1998, T = 293(2) K.

Solvothermal reaction assisted with microwave leads to the formation of two unique heterometallic cubic clusters [Ni{sub 3}M'(L){sub 3}(OH)(CH{sub 3}CN){sub 3}]{sub 2}.CH{sub 3}CN (M'=K for 1 and M'=Na for 2, where L is an anion of 2-[(2-hydroxy-3-methoxy-benzylidene)-amino]-ethanesulfonate) with higher efficiency, yields and purity than those without it. The 6-metallacrown-3 [Ni{sub 3}(OH)(L){sub 3}]{sup -} groups exhibit interesting ion trapping and self-assembly of size-different Na{sup +} and K{sup +} through form recognition and coordination activity in 1 and 2. The magnetic studies for 1 and 2 suggest that the {l_brace}Ni{sub 3}M'O{sub 4}{r_brace} (M'=K and Na) cores both display dominant ferromagnetic interactions from the nature of the binding modes of mu{sub 3}-O (oxidophenyl) and mu{sub 3}-OH. - Graphical abstract: Solvothermal reaction assisted with microwave leads to two heterometallic cubic clusters with 6-metallacrown-3 structure [Ni{sub 3}O{sub 3}(OH)]{sup -} acting as a host for a K{sup +} or Na{sup +} ion. The {l_brace}Ni{sub 3}M'O{sub 4}{r_brace} (M'=K, Na) cores display dominant ferromagnetic interactions.

An important aspect of chemical reactions involves understanding the intermediate steps from reactants to products. The iterative use of mass spectrometry and X-Ray crystallography is demonstrated to be a powerful combination in this respect. We have applied them in identifying molecular clusters in solution followed by their solid-state structural characterizations. We used a key ligand, 2-[(2-hydroxy-3-methoxy-benzylidene)-amino]-ethanesulfonate (L), which serves as chelating/bridging units to stabilize the precursor [Li₄Ni₆(OH)₂(L)₆(CH₃CN)₆](ClO₄)₂·4CH₃CN. The results of subsequent reactions witness a cascade of processes involving fragmentation, inner bridging ligand substitution (OH⁻ to OCH₃⁻), changing modes of binding (chelate to monodentate) of the key ligand, ion-trapping and exchange (Li⁺, Na⁺ and Ca²⁺) and their site preferences, coordinating and non-coordinating solvents (CH₃CN to CH₃OH, H₂O and EtOH) replacement. The flexibility of the Ni₃OL₃ species in solution permits the formation of six derivatives. The complimentary techniques open a broader prospect for cluster design and applications.

The dinuclear title compound, [Pb(2)(C(6)H(8)O(4))(NO(3))(2)(C(19)H(13)N(5))(2)], lies with the mid-point of the butyl chain of the bridging adipate unit on a center of inversion. The Pb(II) ion is covalently bonded to the nitrate anion and is bonded to a carboxyl-ate group of the adipate unit by another covalent bond. The N-heterocycle functions in a chelating tridentate mode. The metal atom exists in a Ψ-octa-hedral coordination environment. When weaker Pb⋯O inter-actions are also considered, the geometry is a Ψ-tricapped trigonal prism in which the lone-pair electrons occupy one face of the trigonal prism. Adjacent mol-ecules are linked into a layer structure by N-H⋯O hydrogen bonds.

The dinuclear title compound, [Pb2(C6H8O4)(NO3)2(C19H13N5)2], lies with the mid-point of the butyl chain of the bridging adipate unit on a center of inversion. The PbII ion is covalently bonded to the nitrate anion and is bonded to a carboxyl­ate group of the adipate unit by another covalent bond. The N-heterocycle functions in a chelating tridentate mode. The metal atom exists in a Ψ-octa­hedral coordination environment. When weaker Pb⋯O inter­actions are also considered, the geometry is a Ψ-tricapped trigonal prism in which the lone-pair electrons occupy one face of the trigonal prism. Adjacent mol­ecules are linked into a layer structure by N—H⋯O hydrogen bonds.