Dominant Role of C−Br···N Halogen Bond in Molecular Self-Organization. Crystallographic and Quantum-Chemical Study of Schiff-Base-Containing Triazoles
摘要:
Three Schiff-base-containing triazole derivatives have been synthesized and investigated by X-ray crystallography. Structural motifs (zigzag or linear chains) formed in the solid state are stabilized by C-Br...N halogen bond interactions, while hydrogen bonds do not seem to play a significant role in the molecular self-organization of studied compounds. Quantum-chemical studies confirm that these interactions are sufficient to account for both the arrangement of structural motifs and very short Br...N distances observed experimentally. It is also shown that Br...N interactions can lead to generally shorter donor-acceptor distances than Cl...N contacts.
Copper‐Catalyzed Aerobic Oxidative CH Functionalization of Substituted Pyridines: Synthesis of Imidazopyridine Derivatives
作者:Jipan Yu、Yunhe Jin、Hao Zhang、Xiaobo Yang、Hua Fu
DOI:10.1002/chem.201302737
日期:2013.12.2
practical method for the synthesis of imidazopyridine derivatives has been developed through the copper‐catalyzed aerobic oxidativeCH functionalization of substitutedpyridines with N‐(alkylidene)‐4H‐1,2,4‐triazol‐4‐amines. The procedure occurs by cleavage of the NN bond in the N‐(alkylidene)‐4H‐1,2,4‐triazol‐4‐amines and activation of an aryl CH bond in the substitutedpyridines. This is the first example
Three Schiff-base-containing triazole derivatives have been synthesized and investigated by X-ray crystallography. Structural motifs (zigzag or linear chains) formed in the solid state are stabilized by C-Br...N halogen bond interactions, while hydrogen bonds do not seem to play a significant role in the molecular self-organization of studied compounds. Quantum-chemical studies confirm that these interactions are sufficient to account for both the arrangement of structural motifs and very short Br...N distances observed experimentally. It is also shown that Br...N interactions can lead to generally shorter donor-acceptor distances than Cl...N contacts.