| Abstract: | Acetylpyridine thiosemicarbazone, HAPTSC ( 1 ), reacts with uranyl nitrate in MeOH under formation of (H2APTSC) [UO2(NO3)2(μ‐OH)]2 ( 2 ) or [ UO2(APTSC)(MeOH)(MeO)]2 ( 3 ) depending on the experimental conditions applied. Protonation of 1 and precipitation of the [UO2(NO3)2(μ‐OH)]22— dianion as acetylpyridinium thiosemicarbazone salt is observed when the reaction is performed without the addition of a base. The metal atoms are situated in the centres of distorted hexagonal bipyramids. The U—U distance is 3.892(1)Å. Addition of triethylamine results in deprotonation of HAPTSC and the formation of 3 which is an unusual dimer with four methanol/methanolato ligands of two metal sites sharing two protons. The U—U distance in this dimer is 5.313(1)Å. (Bu4N)[UO (APTSC)Cl2] ( 4 ) is obtained when (Bu4N)2[UO2Cl4] is used as precursor. The uranium atoms in 3 and 4 are seven co‐ordinate. Their co‐ordination polyhedra can best be described as pentagonal bipyramids. Compounds 3 and 4 represent the first examples of thiosemicarbazone complexes with actinide elements which haven been studied by X‐ray analysis. |
