Thiodiacetate cobalt(II) complexes: Synthesis, structure and properties

Novel cobalt thiodiacetate complexes [Co(tda)(H2O)]n (1a) and [Co(tda)(H2O)3] (1b) (tda=S(CH2COO)22-) were obtained from the reaction of aqueous solutions of cobalt dichloride with a 1:1 mixture of Na2CO3 and thiodiacetic acid. The reactivity of 1a versus 2,2′-bipyridine (bipy) and bis(2-pyridyl)ketone gave compounds [Co(tda)(bipy)(H2O)] · 4H2O (2) and [Co{OC(OH)(2-pyridyl)2}2]+[Htda]− · 3H2O (3), respectively, which were identified by X-ray analysis. 2 is, to our knowledge, the first structural characterization of a cobalt-thiodiacetate complex.