An efficient ultrasonic-assisted synthesis of imidazolium and pyridinium salts based on the Zincke reaction
作者:Sanhu Zhao、Xiaoming Xu、Lu Zheng、Hai Liu
DOI:10.1016/j.ultsonch.2009.12.019
日期:2010.4
irradiation for the synthesis of imidazolium and pyridinium salts based on the Zinckereaction. Tertiary nitrogen nucleophiles such as pyridines and imidazoles can be alkylated with primary amine by simply using their ammonium form Zincke salts. In almost all cases, a clear yield increase results and a dramatic reduction of the reaction time accompanied by an improved quality of the products occurs.
engaged in Zinckereactions. Efficient transformations were obtained, even when conducted on electronically deactivated, eventually also sterically hindered, substrates. This was achieved by the combined use of microwave activation and aqueous solvents. Under our conditions, the role of water revealed indeed crucial to avoid the self-degradation of the Zincke salt, the reagent of the reaction.
Complex Salts of TCNQ with Substituted Phenyl Pyridines and Their Characterization by Scanning Tunneling Microscopy
作者:S. N. Magonov、G. Bar、H.-J. Cantow、D. Kabbeck-Kupijai、G. Koßmehl
DOI:10.1002/bbpc.19930971110
日期:1993.11
AbstractNew conductive complex salts of tetracyanoquinodimethane (TCNQ) with substituted phenylpyridines have been prepared and characterized by optical microscopy, conductivity measurements, X‐ray powder diagrams and scanning tunneling microscopy (STM). The molecular stacking, which is responsible for the one‐dimensional conductivity, was revealed from the diffraction data and STM images. The analysis of the STM images was based on the results obtained on a model compound, the complex salt of TCNQ and quinolinium. Although in STM the surface partial electron density is measured, several crystallographic parameters of the molecular arrangement have been determined from these images.
Grigor'ewa; Petschka, Zhurnal Obshchei Khimii, 1958, vol. 28, p. 1677,1680;engl.Ausg.S.1726,1728
作者:Grigor'ewa、Petschka
DOI:——
日期:——
KATRITZKY A. R.; SAMMES M. P., J. CHEM. SOC. CHEM. COMMUNS <CCOM-A8>, 1975, NO 7, 247-248