Syntheses and properties of the lead 1,3-dithiole-2-thione-4,5-dithiolate (DMIT) compounds: Ph2Pb(DMIT), [Q] [Ph2Pb(DMIT) 1] [Q = NEt4 OR 1,4-Me2-pyridinium], (Ph3Pb)2(DMIT) and Pb(DMIT)

Article abstract of DOI:10.1016/0277-5387(95)00433-5

Syntheses of Ph₂Pb(dmit) (3), [Q] [Ph₂Pb(dmit)1] (5, Q = NEt₄ or 1,4-Me₂-pyridinium), (Ph₃Pb)₂(dmit) (4) and Pb(dmit) (6) are reported [H₂-dmit = 4,5-dimercapto-1,3-dithiole-2-thione]. Compound 3 was produced from Ph₂Pb(OAc)₂ and [NEt₄]₂[Zn (dmit)₂], while 4 was obtained from Ph₃PbOAc and either Na₂(dmit) or [NEt₄]₂[Zn(dmit)₂]. The ionic species, 5, were obtained by addition of [Q] 1 to 3 (eg. for Q = 1,4-Me₂-pyridinium) or from reaction of Ph₂PbI₂ with [NEt₄]₂[Zn(dmit)₂]. Reaction of either Pb(OAc)₂ or Pb(NO₃)₂ with [NEt₄]₂[Zn(dmit)₂] produced 6. NMR spectra, including the solid state spectra for 3, have been obtained. X-ray crystallography revealed 4 to be a monomeric compound with each Pb atom having a distorted tetrahedral geometry. The C - Pb - S bond angles are less and the C - Pb - C bond angles greater than ideal tetrahedral angles. The dmit ligand is effectively inserted between two phenyl rings of different Ph₃Pb groups in 4, with short non-bonded C - C and C - S distances of 3.4-3.7 A. Cyclic voltammetric studies of 3 and of 4 in DMF have also been carried out.