Metal chelates derived from 2,4-Bis-(2-pyridyl)thiazole and 2-(2-pyridylamino)-4-(2-pyridyl)thiazole

Abstract

The bases 2,4-bis-(2-pyridyl)thiazole and 2-(2-pyridylamino)-4-(2-pyridyl)thiazole have been prepared by an adaptation of the Hantzsch thiazole synthesis. Each of these bases is capable of functioning as a tridentate chelating agent and yields well-defined chelates with iron(II), coba1t(II), nickel(II), and copper(II) salts. Complexes of the former base are the less stable and this has been ascribed to greater distortion of its bond angles induced on coordination. Neither base yields complexes of comparable stability to corresponding complexes of terpyridine. The complexes of Fe(II), Co(II), and Ni(II) isolated are spin-free.