Preparations and crystal structures of Sn(CH2CH2CO2Me)2(C3S5) and [Q][Sn(CH2CH2CO2Me)(C3S5)2](Q = NEt4 or 1,4-dimethylpyridinium, C3S5= 4,5-disulfanyl-1,3-dithiole-2-thionate)

Abstract

The compounds Sn(CH₂CH₂CO₂Me)₂(C₃S₅)1(R = Me or Prⁱ) and [Q][Sn(CH₂CH₂CO₂Me)(C₃S₅)₂]2(Q = NEt₄ or 1,4-dimethylpyridinium; C₃S₅= 4,5-disulfanyl-1,3-dithiole-2-thionate) have been prepared and characterised by solution and solid-state NMR spectroscopy. A crystal structure determination of 1(R = Me) revealed it to be a monomeric six-co-ordinate, distorted-octahedral complex with chelating MeO₂CCH₂CH₂ groups and trans-carbon atoms [Sn–O(C) 2.629(7)Å]. The MeO₂CCH₂CH₂ group in 2, both in solution and in the crystal, is monodentate: the tin centres in the anions of both complexes 2 were shown to have structures closer to rectangular pyramids than to trigonal bipyramids. There were, however, slight differences in the solid-state structures of the anions, particularly in regard to the separations of the Sn and carbonyl oxygen atoms; Sn ⋯ O intramolecular distances are 4.84(1) and 3.371(4)Å in 2(Q = NEt₄) and 2(Q = 1,4-dimethylpyridinium) respectively. There were also differences in the packing of the anions.