Structural diversity of cadmium(II) complexes of tetraorganodichalcogenoimidodiphosphinato ligands: Monomeric Cd[(SPMe2)2N]2, dinuclear [Cd{(OPMe2)(SPPh2)N}2]2 and [Cd2{(OPPh2)2N}4(H2O)], and trinuclear K[Cd2{(OPPh2)2N}5]
摘要:
`Cadmium complexes of the type Cd[(XPR2)(YPR2')N](2) (X, Y = O, S; R, R' = Me, Ph) were obtained by reacting CdCl2 and K[(XPR2)(YPR2')N] in a 1:2 molar ratio. The compounds were characterized by IR, multinuclear NMR (H-1, C-13, P-31) spectroscopy and mass spectrometry. The molecular structures of Cd[(SPMe2)(2)N](2) (1), Cd[(OPMe2)(SPPh2)N](2) (4), Cd-2{(OPPh2)(2)N}(4)(H2O)](7 center dot H2O) and K[Cd-2{(OPPh2)(2)N)(5)] (8) were established by single-crystal X-ray diffraction. Colourless crystals of 8 were isolated, along with those of 7-H2O, during recrystallization of crude Cd[(OPPh2)(2)N](2) (7). A monomeric structure with a tetrahedral CdS4 core is found for 1, whereas 4 contains discrete dimers formed through two O,O', S-bimetallictriconnective ligand units resulting in distorted trigonal bipyramidal CdO3S2 Cores. In the dinuclear compound 7 center dot H2O the Cd atoms are also bridged by two O, O', O'-bimetallic triconnective ligands, but the coordination of the metal centres is completed by a bridging water molecule to give distorted octahedral CdO6 cores. in the trimetallic unit of 8 the K atom is accommodated in the cavity described by the oxygen atoms of three ligand units which bridge the Cd atoms. The remaining two ligands are each one chelating a Cd atom, thus resulting in distorted square pyramidal CdO5 cores. (c) 2005 Elsevier B.V. All rights reserved.