Mono Complexes of 2,2'-Bipyridine and 1,10-Phenanthroline with Metal Halides

Abstract

The mono complexes of 2,2'-bipyridine and 1,10-phenanthroline with the halides of Cr(III), Mn(II), and Ni(II) have been prepared in good yield by reaction of the base with excess of the anhydrous metal halide in boiling dimethylformamide solution. The Fe(II) complexes, which could not be prepared satisfactorily in this manner, were made in boiling normal hydrochloric acid, and salted out with solid calcium chloride. The magnetic moments showed that all were of the high-spin type. The high moments of FebipyCl₂ and FephenCl₂ (5.72 and 5.79 B.M.) suggest that the previous value for FephenCl₂ (1.8 B.M.) is in error, and that the change from high- to low-spin does not occur until the third molecule of the ligand has been attached.