Defective double-cubane, tetranuclear manganese(II) and cobalt(II) complexes with simultaneous mu(1,1)-Azido and mu-O bridges

Abstract

The reactions of M(O2CCH(3))(2). 4H(2)O (M= Mn, Co) with di-2-pyridyl ketone, (py)(2)CO, and NaN3 in CH3OH or CH3OH/ H2O allow isolation of the tetranuclear compounds [Mn-4(mu (1.1)-N-3)(2)(N-3)(2)(py)(2)C(OH)O(2)(py)(2)C(OCH3)O(2)] (1) and [Co-4(mu (1.1)-N-3)(2)(N-3)(2)(py)(2)C(OH)O(2)(py)(2)C(OCH3)O(2)]. 2H(2)O (2). X-ray diffraction analysis reveals defective double-cubane tetrameric entities in which the Mn-II or Co-II atoms are linked by mu (1.1)-N-3 bridges and two kinds of O-bridges. The molar magnetic susceptibility measurements of 1 and 2 in the 2-300 K range indicate weak antiferromagnetic coupling for 1 and clear bulk ferromagnetic coupling for 2