Chlorodiphenyltin(IV) and triphenyltin(IV) complexes of N-alkylated 2-amino-1-cyclopentene-1-carbodithioic acids: synthesis, spectroscopic characterization and X-ray studies

Four new complexes, Ph₃Sn(isopropylACDA)] (1), Ph₂SnCl(isopropylACDA)] (2), Ph₃Sn(secbutylACDA)] (3), and Ph₂SnCl(secbutylACDA)] (4), have been prepared from reaction between N-alkylated 2-amino-1-cyclopentene-1-carbodithioic acids (ACDA) with Ph₂SnCl₂ and Ph₃SnCl in 1:1 ratio. All complexes are characterized by FTIR, multinuclear NMR (¹H, ¹³C, and ¹¹⁹Sn) and mass spectrometry. In all complexes, the S–H proton has been removed and coordination takes place through the carbodithioate moiety. The ¹¹⁹Sn NMR data are consistent with five coordination of tin atom in solution. Complexes 2, 3, and 4 have also been confirmed by single X-ray crystallography. All three crystals are triclinic with space group P − 1. In complexes 2 and 4, the geometry around tin atom is distorted trigonal bipyramidal while in 3 the geometry is in between distorted tetrahedral and trigonal bipyramid. In all three structures, ligands are asymmetrically coordinated to tin atom. In addition, crystal structures are further stabilized by N–H···S hydrogen bonding.