Dietmar Stalke

Syntheses of group 7 metal carbonyl complexes with a stable N-heterocyclic chlorosilylene.

Two structurally characterized manganese [L(2)Mn(CO)(4)](+)[Mn(CO)(5)](-) (1) and rhenium [L(3)Re(CO)(3)](+)[ReCO)(5)](-) (2) silylene complexes were prepared in one pot syntheses by reacting 1 equivalent of Mn(2)(CO)(10) with 2 equivalents of stable N-heterocyclic chlorosilylene L {L = PhC(NtBu)(2)SiCl} and 1 equivalent of Re(2)(CO)(10) with 3 equivalents of L in toluene at room temperature. Both complexes 1 and 2 were characterized by single-crystal X-ray structural analysis, NMR and IR spectroscopy, EI-MS spectrometry, and elemental analysis.

Polyimido sulphur anions S(NR) n m− : Free radicals and coordination behaviour

In a reaction sequence of amide addition followed by halogen oxidation the triazasulphite S(NR)32− and the tetrazasulphate S(NR)42− are readily accessible from sulphur diimide S(NR)2 via sulphur triimide S(NR)3. Addition of lithium organics to sulphur triimide provides a general route to triazasulphonates RS(NR)32−. All these anions resemble potential tripodal coordination behaviour because of their nitrogen donor centres. Furthermore, the sulphur polyimido ligands are capable of responding to the various requirements of different metals (even in mixed metal species) by charge (de)localization. This paper deals with the synthetic routes of the sulphur nitrogen anions and their coordination behaviour. Their reactivity, mainly towards main group metal synthons, is also discussed.

Elegant approach to spacer arranged silagermylene and bis(germylene) compounds

Herein we report on the reactions of the stable LSiCl (1) and LGeCl (2) [L = PhC(NtBu)(2)] with L(1)Ge, [L(1) = CH{(C[double bond, length as m-dash]CH(2))(CMe)(2,6-iPr(2)C(6)H(3)N)(2)}] (3) to yield 1-sila-5-germylene (4) and a 1,5-bis(germylene) (5). The reactions proceed through the 1,4 nucleophilic addition of the M-Cl (M = Si or Ge) to 3 without any modification of the oxidation state although the change of the oxidation state is thermodynamically more favorable. Compounds 4 and 5 were investigated by single crystal X-ray structural analyses, multi-nuclear NMR spectroscopy, and micro-analysis. Treatment of L(1)AlMe·thf (6) with 1 resulted in the formation of the 1-sila-5-aluminium complex (7). The complex contains a Si(II) and an Al(III) atom in the molecule. All reported reactions proceed without changing the oxidation states at the metal centers.

Novel Multidentate Sulfur–Nitrogen Ligands with Enhanced Complexation Properties

Di(tert-butyl)sulfur diimide and bis(trimethylsilyl)sulfur diimide were reacted with different metalated amines to form versatile novel multidentate ligand systems with side-arm donation. Their complexation properties in terms of ligand design, denticity and the cation size are discussed. We report herein the synthesis and structure elucidation of [(tBuN)(2)S{LiMe(2)N(C(6)H(4))S(NtBu)(2)}(2)] (1), [(Li{Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (2), [(Li(thf){Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (3), [(Li{2-PicS(NSiMe(3))(2)})(2)] (4), [(Li{Me(2)N(CH(2))(2)N(Me)S(NSiMe(3))(2)})(2)] (5), [(Na{Me(2)N(CH(2))(2)N(Me)S(NSiMe(3))(2)})(2)] (6) and [(K{Me(2)N(C(6)H(4))S(NSiMe(3))(2)})(2)] (7).