Complexes of the general
formula Mo(CO)2L2X2 (L = pyridine (py), 2,2'-
dipyridyl (dipy), 1,l0-phenanthroline
(phen); X = Cl, Br) have been isolated. The pyrldine
derivatives are yellow monomeric compounds which are paramagnetic, but the
complexes with dipy and phen contain diamagnetic
seven-coordinate cations and are correctly formulated as [Mo(CO)2L2X]+X-.
Conductance, infrared, magnetic, and electron spin resonance studies have been
carried out.