115826-87-4Relevant academic research and scientific papers
Synthesis and molecular structure of a lantern dimer, (AsPh4)2[Tc2O2(SCH 2CONHCH2CH2NHCOCH2S)4]
Bryson, Nathan J.,Brenner, David,Lister-James, John,Jones, Alun G.,Dewan, John C.,Davison, Alan
, p. 3825 - 3828 (2008/10/08)
Reaction of (Bu4N)[TcOCl4] with a 5-fold excess of N,N′-ethylenebis(2-mercaptoacetainide) (H4ema) in methanolic sodium methoxide yielded a blue precipitate which was metathesized to give (AsPh4)2[Tc2O2(H 2ema)4] (1). Complex 1 crystallized as a hexahydrate and was structurally characterized by single-crystal X-ray crystallography. The structure of the dianion showed a centrosymmetric dianion with two square-pyramidal OTcS4 cores bridged 4-fold by the [H2ema2-] dithiolate ligands. The metal-oxo groups are oriented into the center of the cage created by the bridging ligands, giving what is referred to as a lantern structure. The intramolecular Tc-Tc* distance was 7.175 (4) ?, and the distance between the two metal oxo ligands, O1-O1*, was 3.96(2) ?. The six water molecules per dimer were found to be hydrogen-bonded to each other and to the amide NH and CO groups on the ligands. Compound 1 was converted to (AsPh4) [TcO(ema)] when heated in solution or when reacted with aqueous base. Crystal data for 1 are as follows: molecular formula C72H92N8O16As2Tc 2S8, monoclinic, a = 19.099 (4) A*, b = 14.144 (6) ?, c = 15.809 (5) ?, β= 109.17 (2)°, V = 440033.8 ?-3, space group P21/n, Z = 2, final R1 = 0.067, R2 = 0.103.
