Calatayud David G, López-Torres Elena, Mendiola M Antonia
Departamento de Química InorgAnica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Inorg Chem. 2007 Nov 26;46(24):10434-43. doi: 10.1021/ic701490j. Epub 2007 Oct 16.
Reactions of diphenyllead(IV) chloride with benzil bis(thiosemicarbazone) (L1H6) and benzil bis(4-methyl-3-thiosemicarbazone) (L1Me2H4) afforded the first complexes containing the diphenyllead(IV) moiety with bis(thiosemicarbazone) ligands. The new complexes show diverse structural characteristics depending on the ligand and the working conditions. Complexes [PbPh2Cl(L1H5)].3H2O (1) and [PbPh2Cl(L1Me2H3)] (3) are mononuclear species in which the ligands are partially deprotonated and the lead atom has a C2N2S2Cl environment in a distorted pentagonal bipyramid coordination geometry. Complex PbPh(L1Me2H2).2H2O (4) was also obtained, which contains two lead atoms in a binuclear structure with a C2N2S3 coordination sphere for each lead atom, since both dideprotonated ligands act as N2S2 chelate and as sulfur bridge. Reaction from L1H6, in the same conditions in which complex 4 was prepared, gave a mixture of products: the lead (II) complex [Pb(L1H4)]2 (2) and [PbPh3Cl]n. Reactions with the cyclic molecules 5-methoxy-5,6-diphenyl-4,5-dihydro-2H-[1,2,4]-triazine-3-thione (L2H2OCH3) and 5-methoxy-4-methyl-5,6-diphenyl-4,5-dihydro-2H-[1,2,4]-triazine-3-thione (L2MeHOCH3) were also explored. In all the complexes, the ligands are deprotonated. The complexes [PbPh2(L2)2] (5) and [PbPh2(L2MeOCH3)2] (7) present the same characteristics. The X-ray structure of 5 shows a distorted octahedral geometry around the lead atom, with the ligand molecules acting as NS chelates, but the nitrogen bonded to the metal is different; one of the triazines shows a novel behavior, since the nitrogen atom of the new imine group formed is the one that is bonded to the lead center, being a good example of linkage isomerism. The complex [PbPh2Cl(L2)] (6), which was also isolated, could not be crystallized. All the complexes were characterized by elemental analysis, mass spectrometry, IR and 1H, 13C, and 207Pb NMR spectroscopy and some of them by X-ray diffraction studies.
二氯化二苯基铅(IV)与联苯甲酰双(硫代氨基脲)(L1H6)和联苯甲酰双(4-甲基-3-硫代氨基脲)(L1Me2H4)反应，得到了首例含有二苯基铅(IV)部分与双(硫代氨基脲)配体的配合物。根据配体和反应条件的不同，这些新配合物呈现出多样的结构特征。配合物[PbPh2Cl(L1H5)].3H2O(1)和PbPh2Cl(L1Me2H3)是单核物种，其中配体部分去质子化，铅原子在扭曲的五角双锥配位几何结构中具有C2N2S2Cl环境。还得到了配合物PbPh(L1Me2H2).2H2O(4)，它在双核结构中含有两个铅原子，每个铅原子具有C2N2S3配位球，因为两个双去质子化的配体既作为N2S2螯合物又作为硫桥。在制备配合物4的相同条件下，L1H6的反应得到了产物混合物：铅(II)配合物[Pb(L1H4)]2(2)和[PbPh3Cl]n。还研究了与环状分子5-甲氧基-5,6-二苯基-4,5-二氢-2H-[1,2,4]-三嗪-3-硫酮(L2H2OCH3)和5-甲氧基-4-甲基-5,6-二苯基-4,5-二氢-2H-[1,2,4]-三嗪-3-硫酮(L2MeHOCH3)的反应。在所有配合物中，配体均去质子化。配合物PbPh2(L2)2和PbPh2(L2MeOCH3)2具有相同的特征。5的X射线结构显示铅原子周围为扭曲的八面体几何结构，配体分子作为NS螯合物，但与金属键合的氮不同；其中一个三嗪表现出一种新行为，因为新形成的亚胺基团的氮原子是与铅中心键合的原子，这是键合异构的一个很好的例子。同样分离得到的配合物PbPh2Cl(L2)无法结晶。所有配合物均通过元素分析、质谱、红外光谱以及1H、13C和207Pb核磁共振光谱进行表征，其中一些还通过X射线衍射研究进行了表征。
