A new rare earth metal and samarium-catalyzed C(sp(3))-H bond activation is reported in which 2-alkylazaarenes and propargylic alcohols were converted to indolizines. This process operates under mild conditions and solvent-free conditions. A broad scope of coupling partners has been established, and a likely mechanism has also been suggested.

Two metallo-complexes inhibited telomerase by interacting with c-myc G4-DNA and induced cell cycle arrest at the S phase.

Sophisticated aggregation assembly is challenging in assembly chemistry. Monitoring the assembly process helps to understand the assembly mechanism and the create new building blocks. A two-dimensional (2D) cluster-based coordination polymer...

By using a new N-heterocyclic building block, 5,5′-di(pyridin-2-yl)-3,3′-bi(1,2,4-triazole) (2,2′-H 2 dbpt), five novel coordination complexes, Fe 4 (2,2′-Hdbpt) 2 Cl 6 (H 2 O) 6 (1), [Fe(2,2′-H 2 dbpt)Cl 2 ·H 2 O] n (2), [Fe(2,2′-H 2 dbpt)Cl 2 ] n (3), [Fe 2 (2,2′-H 2 dbpt)Cl 4 ] n (4), and [Fe(2,2′-H 2 dbpt) 0.5 Cl 2 ] n (5), based on a Fe(II)/Cl system with diversiform connectivity from zero-to two-dimensional (2D) were constructed successfully. By regulating the metal−ligand ratio and solvents, 2,2′-H 2 dbpt changed various coordination modes. Consequently, 1 reveals a discrete Fe 4 (2,2′-Hdbpt) 2 Cl 6 (H 2 O) 6 supramolecule. 2 and 3 are pseudo-polymorphic. 2 reveals a helical chain based on the cis-FeCl 2 N 4 unit and the cis-bridging 2,2′-H 2 dbpt ligand, while 3 reveals a straight-chain based on the trans-FeCl 2 N 4 unit and the transbridging 2,2′-H 2 dbpt ligand. 4 and 5 are also supramolecular isomers. Different from 2 and 3, both of them have a cis-FeCl 2 N 4 unit. Owing to the different rotation angles of pyridine rings in 2,2′-H 2 dbpt, 4 and 5 reveal a one-dimensional modified trapezoid chain based on the trans-bridging 2,2′-H 2 dbpt ligand and a 2D wave-like layer based on the cis-bridging 2,2′-H 2 dbpt ligand, respectively. Furthermore, compound 4 could also be viewed as a wave banded chain constructed by 3 with μ 2 -Cl ions replaced by the terminal Cl ions and water molecules from another perspective. 1 reveals weak antiferromagnetic behavior. 2, and 3 both reveal paramagnetic behavior, while 4 and 5 both reveal ferromagnetic behavior. These results indicate that 2,2′-H 2 dbpt is an excellent multi-connection linker to construct supramolecular coordination complexes with interesting structures and properties. ■ INTRODUCTIONThe design and synthesis of supramolecular coordination complexes have attracted remarkable attention in the realm of supramolecular chemistry and crystal engineering, not only owing to their appealing structural and topological novelty but also because of their tremendous potential applications in gas storage and separation, 1−5 electrical conduction, 6−9 luminescence materials, 10−20 molecular magnets, 21−26 and heterogeneous catalysis. 27−32 However, how to rationally design and synthesize supramolecular coordination complexes with the desired structure and properties is still a challenge up to now. The assembly of such supramolecular systems may be easily affected by many factors, including the coordination geometry of the central metal ions, solvents, 33−35 ligand structure, metal− ligand ratio, 36,37 counterions, 38−40 pH, 41−44 temperature, 45,46 and so on. Among the reported studies, much effort has been focused on the rational design and controlled synthesis of coordination polymers using multidentate ligands such as polycarboxylate acids, phosphonic acids, and organic ligands containing heterocyclic triazolyl groups. 47 5,5′-Di(pyridin-2-yl)-3,3′-bi(1,2,4-triazole)(2,2′-H 2 dbpt) may be a excellent multidentate ligand to construct supramolecular coordination complexes...

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