Abstract
An improved method for the synthesis of carboxamide ligands containing thioether donor sites is described. This replaces the pyridine as the reaction medium used in the classical method by tetrabutylammonium bromide. The desired products, 1,4-bis[o-(R-2-carboxamidophenyl)]-1,4-dithiobutane, R = quinoline (1), furan (2), thiophene (3), pyridine (4), and pyrazine (5), were obtained in good yields and shorter reaction times.
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
Partial support of this work by the Isafan University of Technology (IUT) Research Council is gratefully acknowledged. Also acknowledged is partial support from the U.S. National Science Foundation Grant NSF-CHE-0749524 to P. C. F.