Title:
|
Synthesis and coordination chemistry of new distibine and mixed phospha-thia ligands
|
High yield syntheses of a series of novel distibine ligands are reported, together with detailed investigations into their coordination chemistry with a wide range of transition metals. The xylyl-distibines 1,2-, 1,3- and 1,4-C₆H₄(CH₂SbMe₂)₂ have been prepared by reaction of Me₂SbCl with the appropriate Grignard reagent. The phenylene-distibines 1,3- and 1,4-C₆H₄(SbMe₂)₂ have also been prepared following the same synthetic route. All of the novel ligands and their methiodide derivatives have been characterised by 1H and 13C{1H}NMR spectroscopy, mass spectrometry and microanalysis. Crystal structures of 1,4-C₆H₄(CH₂SbMe₂)₂ and [1,3-C₆H₄(CH₂SbMe₃)₂]I₂ are reported. The synthesis of 1,2-C₆H₄(CH₂SbPh₂)₂ is also described, together with the attempted synthesis of 1,2-C₆H₄(SbPh₂)₂. Iron, tungsten and nickel carbonyl complexes of the above ligands have been prepared and the crystal structure of [{Fe(CO)₄}₂{μ-1,3-C₆H₄(CH₂SbMe₂)₂}] is described. The coordination modes and electronic properties of the novel ligands are investigated in detail and, where appropriate, their spectroscopic properties are compared with other related Group 15 ligands. Complexes of 1,2-C₆H₄(CH₂SbMe₂)₂ with Cu(I), Ag(I), Pt(II), Pd(II), Rh(III), Ni(II) and Co(III) are described. The compounds have been characterised by IR, UV-vis, 1H, 63Cu, and 59Co NMR spectroscopy, mass spectrometry and microanalysis as appropriate. The crystal structures of [CU{1,2-C₆H₄(CH₂SbMe₂)₂}₂][BF₄], [Pt{1,2-C₆H₄(CH₂SbMe₂)₂}₂][PF₆]₂, [Pd{1,2-C₆H₄(CH₂SbMe₂)₂}₂][PF₆]₂, [PtCl₂{1,2-C₆H₄(CH₂SbMe₂)₂}], and [NiI{1,2-C₆H₄(CH₂SbMe₂}₂][(ClO₄] are reported and the ligating behaviour is compared with that of 1,2-C₆H₄(SbMe₂)₂ and related aliphatic-backboned distibines. The coordination chemistry of the mixed donor P/O and P/S ligands Ph₂P(CH₂)₂O(CH₂)₂O(CH₂)₂PPh₂ (L1) and Ph₂P(CH₂)₂S(CH₂)₂S(CH₂)₂PPh₂ (L2) with Ag(I) and Cr(0), Mo(0), W(0), Mn(I) and Re(I) carbonyls is investigated. The coordination modes adopted by the ligands have been probed by 31P{1H} NMR spectroscopy. Crystal structures of [Ag(L1)][CF₃SO₃], [Ag(L1)][ClO₄], [Ag(L1)(NO₃)], [Ag₂(L1)₃][CF₃SO₃]₂ and [Mo(CO)₄(L1)] are reported.
|