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

Neutral diorganotin dmit compounds, R(2)Sn(dmit), have been synthesised from R(2)SnX(2) (R = Me, Et, Bu, octyl, Ph or o-MeOC(6)H(4); R(2) = Ph,Me; X = Cl or Br) and [NEt(4)](2)[Zn(dmit)(2)] (H-2-dmit = 4,5-dimercapto-1,3-dithiole-2-thione, H2C3S5). Solution and solid state NMR spectra have been obtained for selected R(2)Sn(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(5(1)) = 3.139(1) Angstrom; Sn-S(5(1))-C(3(1)) = 111.2(2)degrees). The links between the monomers within the chains are further strengthened by weak S ... S intermonomer interactions, S(5(1)) ... S(2) = 3.315(2) and S(3(1)) ... S(2) = 3.446(2) Angstrom. Furthermore, weaker S ... S interactions (S(5(1)) ... S(1(11)) = 3.635(2) Angstrom) 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) Angstrom) and by a dithiolato sulphur atom (Sn-S(2) = 2.437(1) Angstrom). The axial sites are occupied by the other dithiolato sulphur atom (Sn-S(1) = 2.487(1) Angstrom) and the bridging thione sulphur (S(5(1))): the valency angle, S(5(1))-Sn-S(1), is 161.63(3)degrees with the dithiolate bite angle of 89.92(4)degrees. The R(2)Sn(dmit) compounds react with onium halides, [Q]X to give [Q][R(2)Sn(dmit)X], form complexes, [R(2)Sn(dmit)L], with donors, (e.g. L = bipy, py or DMF), and undergo exchange reactions with R(2)(1)SnCl(2).