N-(Diisopropylthiophosphoryl)-N′-(R)-thioureas: synthesis, characterization, crystal structures and competitive bulk liquid membrane transport of some metal ions

Abstract

Ten N-thiophosphorylated thioureas of the common formula RC(S)NHP(S)(OiPr)(2) [R = iPrNH (1), EtNH (2), Et(2)N (3), 2,5-Me(2)C(6)H(3)NH (4), 4-Me(2)NC(6)H(4)NH (5), 2-MeO(O)CC(6)H(4)NH (6), 2-PyNH (7), 2-PyCH(2)NH (8), 3-PyCH(2)NH (9), cyclo-C(2)H(2)N(3)NH (10)] have been synthesized and characterized by IR, NMR spectroscopy and elemental analysis. Molecular structures of 1 and 4-8 were elucidated by X-ray diffraction revealing linear, bi- or trifurcated intramolecular hydrogen bonds. Additionally, their crystal structures are stabillized by two intermolecular hydrogen bonds, which in turn lead to a centrosymmetric dimer formation. The hydrogen bonded dimers of 5-8 are packed to polymeric chains through the π···π stacking interactions between aryl or pyridyl rings. Competitive transport experiments involving metal ions from an aqueous source phase through a chloroform membrane into an aqueous receiving phase have been carried out using 2-6 and 8-10 as the ionophore present in the organic phase. The source phase contained equimolar concentrations of Co(II), Ni(II), Cu(II), Zn(II), Ag(I), Cd(II) and Pb(II) with the source and receiving phases being buffered at pH = 5.5 and 1.0, respectively. The obtained data were compared with the transport and extraction properties of 1 and 7, which were described recently.

Metal ion influences distortion of the ligand in the structure of [M{2-MeO(O)CC6H4NHC(S)NP(S)(OiPr)2}2] (M = ZnII, CdII) complexes: a driving force for intermolecular aggregation

“…0.73(4) 2.00(4) 2.620 (5) 143 (4) The lengthening of the C-S and P-S and shortening of the C-N(P) and P-N bonds in both complexes, compared with the 65 values for the parent ligand HL, 9 Table 2) in line with the structure concluded from NMR (Scheme 1). A closer inspection of the crystal structures revealed further H•••X hydrogen bonds (Table S1 in the ESI †), however, based on established criteria 14 15 we consider them not to be determining the crystal or molecular structures.…”

“…10 This band is shifted by ~90 cm -1 to low frequencies compared with that in the spectrum of the parent HL. 9 Further bands at 1530 and 1695 cm -1 correspond to the conjugated SCN fragment and C=O group, respectively. In addition, there is a broad intense absorption arising from the POC group at about 970-990 cm -1 .…”

“…[9][10][11] The 1 H NMR spectra of complexes in CDCl 3 each contain one set of signals. The signals of the isopropyl CH 3 protons are observed at about 1.40 ppm, while the aryl CH 3 protons are at 3.90 ppm.…”

“…8 In this contribution we describe the synthesis of new Zn II and Cd II complexes with the N-thiophosphorylated thiourea 2-MeO(O)CC 6 H 4 NHC(S)NHP(S)(OiPr) 2 (HL). 9 We also describe a complete structural investigation of the obtained complexes 55 [ZnL 2 ] and [CdL 2 ] both in solution and solid state together with their thermal properties. The experimental results were supported by detailed quantum chemical calculations.…”

Chiral Thiophosphorylated Thioureas: Synthesis, Structure, and Cyclization Reaction

“…Recently, thiophosphorylated thioureas attracted much attention because the introduction of the thiophosphoryl group into the molecule may add new properties, e.g., the ability to form hydrogen bonds or coordinate metals . These compounds are easily available by the addition of various amines to thiophosphoryl isothiocyanates.…”