Synthesis and Characterization of a Linear [Mn(3)(O(2)CMe)(4)(py)(8)](2+) Complex

Two new compounds that consist of the linear trinuclear manganese(II) cation [Mn(3)(O(2)CMe)(4)(py)(8)](2+) cocrystallizing with different counteranions (I(3) (−), [1]; ClO(4) (−), [2]) are reported. Complex 1 was prepared from the reaction of [Mn(O(2)CMe)(2)] · 4H(2)O with I(2) in MeCO(2)H/py, whereas complex 2 was isolated from the reaction of [Mn(3)O(O(2)CMe)(6)(py)(3)] · py with [Mn(ClO(4))(2)] · 6H(2)O in MeCN/py. The crystal structures of both compounds were determined by single crystal X-ray crystallography. Magnetic susceptibility studies that were performed in microcrystalline powder of 1 in the 2–300 K range revealed the presence of antiferromagnetic exchange interactions that resulted in an S = 5/2 ground spin state.