Crystal structure of catena-poly[aquabis(3-nitrobenzoato-κ2 O:O′)-(μ 2-pyrazine-N: N′)cadmium(II)], C18H14N4O9Cd

C18H14N4O9Cd, monoclinic, C2/c (no. 15), a = 22.390(4) Å, b = 6.2758(13) Å, c = 14.962(3) Å, β = 104.15(3)°, V = 7700.2(10) Å3, Z = 4, R gt (F) = 0.0238, wR ref (F 2) = 0.0539, T = 293 K.

Asymmetric metal–organic frameworks with double helices for enantioselective recognition

A pair of homochiral metal–organic frameworks are elaborated by employing flexible enantiopure ligands.

A pair of 2D chiral Ag(i) enantiomers with dual chiral elements: syntheses, structures, and photoluminescent and chiroptical properties

In this work, two new enantiopure bis-monodentate N-donor chiral ligands, namely (-)/(+)-2-(4'-pyridyl)-4,5-pinene-pyridine (L R /L S ), have been designed and synthesized. Using L R and L S as bridging ligands to react with AgClO4, a pair of novel 2D chiral Ag(i) enantiomers formulated as [Ag2(L R )2(ClO4)2] n (R-1) and [Ag2(L S )2(ClO4)2] n (S-1) were isolated and characterized. In R-1 and S-1, each Ag(i) ion is bonded by two N atoms from two different chiral L R or L S ligands, leading to the formation of 1D right- or left-handed -L-Ag(i)-L- helical chains. Moreover, two adjacent helical chains are further doubly linked by two monodentate ClO4 - anions through weak Ag-O contacts to form 2D network structures, in which dual chiral elements, i.e., center chirality and helical chirality coexist. Interestingly, each free ligand L R /L S and R-1/S-1 enantiomers show very different ECD spectra in the solid state and in solution, which are correlated to the intermolecular interactions and molecular structures in each state, respectively. Notably, as a representative, R-1 exhibits intense room temperature photoluminescence both in the solid state and in solution with different emission features and mechanisms, while it also shows more intense emission than that of free ligand L R . In particular, R-1 and S-1 represent the first examples of 2D Ag(i) chiral coordination polymers (CCPs) supported by ClO4 - anions, possessing dual chiral elements.

Synthesis and photocatalytic activities of two homochiral metal–organic frameworks with cages and hydrogen bonding helices

Two homochiral metal–organic frameworks with M₃L₂ cages exhibit interesting hydrogen bonding helices and excellent photocatalytic activity.

Three helical chain-based 3D coordination polymers: solvent-induced syntheses, tunable structures and catalytic properties for the Strecker reaction

Three 3D Sc-CPs with different helical chains have been synthesized from isophthalic acid derivatives by solvent induced methods. Among them, 3 is optically active. Furthermore, 1 exhibits good catalytic activity for the Strecker reactions.