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Four new metal–organic frameworks (MOFs), {[Zn3(L)(OH)(H2O)5]·NMP·2H2O}n (1), {[H2N(Me)2][Zn2(L)(H2O)]·DMF·H2O}n (2), {[Co5(L)2(H2O)11]·2H2O}n (3) and {[Mn5(L)2(H2O)12]·6H2O}n (4), were assembled employing a symmetrical V-shaped rigid multicarboxylic acid ligand H5L (H5L = 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid) with different metal ions, resulting in versatile frameworks as well as various types of coordination modes of H5L. 1 forms a three-dimensional (3D) 4-connected sra net based on trinuclear [Zn3(μ3-OH)(μ2-COO)(μ1-COO)4] clusters, while 2 displays a 3D (4,6)-connected net based on two types of binuclear [Zn2(μ2-COO)2(μ1-COO)4] and [Zn2(μ2-COO)4] clusters. 3 and 4 contain similar [M3(μ2-COO)4(μ1-COO)2] (3, M = Co; 4, M = Mn) clusters but result in different 4-connected 3D and 2D frameworks, respectively. 1 and 2 show solid-state luminescence properties at ambient temperature. Meanwhile, 1 shows high selectivity and sensitivity for not only Fe3+ cations but also for CrO42−, Cr2O72− and MnO4− anions via a luminescence quenching effect with a low detection limit, which thus means that it could be a potential crystalline material for detecting these anions. The mechanisms of the quenching effect and sensing properties of 1 are discussed in detail. In addition, 3 and 4 have the presence of antiferromagnetic interactions between the metal ions. [ABSTRACT FROM AUTHOR]

Six new complexes based on 5-(triazol-1-yl)nicotinic acid (HL), namely [Cu2(L)3(H2O)(OH)]n (1), [Co(L)2(H2O)2]n (2), [Mn(L)2(H2O)2]n (3), {[Co(L)(H2O)0.5(DMF)0.5(NO3)0.5]·(Cl)0.5·DMF·2H2O}n (4), {[Cu(L)(O)0.5]·CH3OH·2.5H2O}n (5) and {[Co2(L)4(H2O)]·2DMA·2H2O}n (6), were synthesized under hydro(solvo)thermal conditions. The L− ligand in 1–6 reveals various coordination modes and forms diverse secondary building units (SBUs) in the final structures. Complex 1 shows a 2D layered structure with a rare (3,8)-connected topology based on tetranuclear [Cu4(COO)6(H2O)2(OH)2N6] SBUs. 2 and 3 are isostructural and display 2D 4-connected sql nets with a point symbol of (44·62). 4 and 5 have similar spatial 3D porous frameworks, which can be simplified as a (3,6)-connected 2-nodal net via dinuclear [Co2(COO)2(O)2(NO3)(N)4] SBUs and [Cu2(COO)2(O)(N)4] SBUs, respectively. 6 is a 3D porous framework constructed by dinuclear [Co2(COO)4(H2O)(N)4] motifs with a uninodal 4-connected qtz net. The magnetic properties and gas sorption behaviour of these complexes were investigated carefully, showing that 3 exhibits ferrimagnetic character and 4 demonstrates its effective storage capacity for CO2 as well as high selectivity for CO2 over CH4 under ambient conditions. [ABSTRACT FROM AUTHOR]

Four new metal-organic frameworks (MOFs), {[Zn 3 (L)(OH)(H 2 O) 5 ]·NMP·2H 2 O} n (1), {[H 2 N(Me) 2 ][Zn 2 (L)(H 2 O)]·DMF·H 2 O} n (2), {[Co 5 (L) 2 (H 2 O) 11 ]·2H 2 O} n (3) and {[Mn 5 (L) 2 (H 2 O) 12 ]·6H 2 O} n (4), were assembled employing a symmetrical V-shaped rigid multicarboxylic acid ligand H 5 L (H 5 L = 2,4-di(3',5'-dicarboxylphenyl)benzoic acid) with different metal ions, resulting in versatile frameworks as well as various types of coordination modes of H 5 L. 1 forms a three-dimensional (3D) 4-connected sra net based on trinuclear [Zn 3 (μ 3 -OH)(μ 2 -COO)(μ 1 -COO) 4 ] clusters, while 2 displays a 3D (4,6)-connected net based on two types of binuclear [Zn 2 (μ 2 -COO) 2 (μ 1 -COO) 4 ] and [Zn 2 (μ 2 -COO) 4 ] clusters. 3 and 4 contain similar [M 3 (μ 2 -COO) 4 (μ 1 -COO) 2 ] (3, M = Co; 4, M = Mn) clusters but result in different 4-connected 3D and 2D frameworks, respectively. 1 and 2 show solid-state luminescence properties at ambient temperature. Meanwhile, 1 shows high selectivity and sensitivity for not only Fe 3+ cations but also for CrO 4 2- , Cr 2 O 7 2- and MnO 4 - anions via a luminescence quenching effect with a low detection limit, which thus means that it could be a potential crystalline material for detecting these anions. The mechanisms of the quenching effect and sensing properties of 1 are discussed in detail. In addition, 3 and 4 have the presence of antiferromagnetic interactions between the metal ions.

Six new complexes based on 5-(triazol-1-yl)nicotinic acid (HL), namely [Cu 2 (L) 3 (H 2 O)(OH)] n (1), [Co(L) 2 (H 2 O) 2 ] n (2), [Mn(L) 2 (H 2 O) 2 ] n (3), {[Co(L)(H 2 O) 0.5 (DMF) 0.5 (NO 3 ) 0.5 ]·(Cl) 0.5 ·DMF·2H 2 O} n (4), {[Cu(L)(O) 0.5 ]·CH 3 OH·2.5H 2 O} n (5) and {[Co 2 (L) 4 (H 2 O)]·2DMA·2H 2 O} n (6), were synthesized under hydro(solvo)thermal conditions. The L - ligand in 1-6 reveals various coordination modes and forms diverse secondary building units (SBUs) in the final structures. Complex 1 shows a 2D layered structure with a rare (3,8)-connected topology based on tetranuclear [Cu 4 (COO) 6 (H 2 O) 2 (OH) 2 N 6 ] SBUs. 2 and 3 are isostructural and display 2D 4-connected sql nets with a point symbol of (4 4 ·6 2 ). 4 and 5 have similar spatial 3D porous frameworks, which can be simplified as a (3,6)-connected 2-nodal net via dinuclear [Co 2 (COO) 2 (O) 2 (NO 3 )(N) 4 ] SBUs and [Cu 2 (COO) 2 (O)(N) 4 ] SBUs, respectively. 6 is a 3D porous framework constructed by dinuclear [Co 2 (COO) 4 (H 2 O)(N) 4 ] motifs with a uninodal 4-connected qtz net. The magnetic properties and gas sorption behaviour of these complexes were investigated carefully, showing that 3 exhibits ferrimagnetic character and 4 demonstrates its effective storage capacity for CO 2 as well as high selectivity for CO 2 over CH 4 under ambient conditions.

A general and efficient BiCl3-catalyzed substitution reaction of propargylic alcohols with carbon and heteroatom-centered nucleophiles such as allyl trimethylsilane, alcohols, aromatic compounds, thiols and amides, leading to the construction of C-C, C-O, C-S and C-N bonds, has been developed.