Diorganotin 1,3-dithiole-2-thione-4,5-dithiolate compounds, R2Sn(dmit): The crystal structure of MePhSn(dmit)

Article abstract of DOI:10.1016/0022-328X(96)06139-6

Neutral diorganotin dmit compounds, R₂Sn(dmit), have been synthesised from R₂SnX₂ (R = Me, Et, Bu, octyl, Ph or o-MeOC₆H₄; R₂ = Ph,Me; X = Cl or Br) and [NEt₄]₂[Zn(dmit)₂] (H₂-dmit = 4,5-dimercapto-1,3-dithiole-2-thione, H₂C₃S₅). Solution and solid state NMR spectra have been obtained for selected R₂Sn(dmit) species as has the crystal structure of MePhSn(dmit) 10. Molecules of 10 in the solid state are linked into zig-zag chains via Sn ... thione S intermolecular associations (Sn-S(5¹) = 3.139(1) A; Sn-S(5¹)-C(3¹) = 111.2(2)°). The links between the monomers within the chains are further strengthened by weak S ... S intermonomer interactions, S(5¹) ... S(2) = 3.315(2) and S(3¹) ... S(2) = 3.446(2) A. Furthermore, weaker S ... S interactions (S(5¹) ... S(1¹¹) = 3.635(2) A) link the chains. The geometry at tin is distorted trigonal bipyramidal; with the equatorial sites occupied by the organic groups (Sn-C = 2.111(5) and 2.134(2) A) and by a dithiolato sulphur atom (Sn-S(2) = 2.437(1) A). The axial sites are occupied by the other dithiolato sulphur atom (Sn-S(1) = 2.487(1) A) and the bridging thione sulphur (S(5¹)): the valency angle, S(5¹)-Sn-S(1), is 161.63(3)° with the dithiolate bite angle of 89.92(4)°. The R₂Sn(dmit) compounds react with onium halides, [Q]X to give [Q][R₂Sn(dmit)X], form complexes, [R₂Sn(dmit)L], with donors, (e.g. L = bipy, py or DMF), and undergo exchange reactions with R¹₂SnCl₂.