(N,N-Diallyldithiocarbamato-κ2 S,S′)triphenyltin(IV) and bis(N,N-diallyldithiocarbamato-κ2 S,S′)diphenyltin(IV): crystal structure, Hirshfeld surface analysis and computational study

Abstract

The crystal and molecular structures of the title organotin dithiocarbamate compounds, [Sn(C6H5)3(C7H10NS2)] (I) and [Sn(C6H5)2(C7H10NS2)2] (II), present very distinct tin atom coordination geometries. In (I), the dithiocarbamate ligand is asymmetrically coordinating with the resulting C3S2 donor set defining a coordination geometry intermediate between square-pyramidal and trigonal–bipyramidal. In (II), two independent molecules comprise the asymmetric unit, which differ in the conformations of the allyl substituents and in the relative orientations of the tin-bound phenyl rings. The dithiocarbamate ligands in (II) coordinate in an asymmetric mode but the Sn—S bonds are more symmetric than observed in (I). The resulting C2S4 donor set approximates an octahedral coordination geometry with a cis-disposition of the ipso-carbon atoms and with the more tightly bound sulfur atoms approximately trans. The only directional intermolecular contacts in the crystals of (I) and (II) are of the type phenyl-C—H...π(phenyl) and vinylidene-C—H...π(phenyl), respectively, with each leading to a supramolecular chain propagating along the a-axis direction. The calculated Hirshfeld surfaces emphasize the importance of H...H contacts in the crystal of (I), i.e. contributing 62.2% to the overall surface. The only other two significant contacts also involve hydrogen, i.e. C...H/H...C (28.4%) and S...H/H...S (8.6%). Similar observations pertain to the individual molecules of (II), which are clearly distinguishable in their surface contacts, with H...H being clearly dominant (59.9 and 64.9%, respectively) along with C...H/H...C (24.3 and 20.1%) and S...H/H...S (14.4 and 13.6%) contacts. The calculations of energies of interaction suggest dispersive forces make a significant contribution to the stabilization of the crystals. The exception is for the C—H...π contacts in (II) where, in addition to the dispersive contribution, significant contributions are made by the electrostatic forces.