Synthesis, Characterization, And Properties Study Of N,N-Diethylammounium O,O’-Dialkyl-Dithiophosphate And Their Complexes

Eight N,N-diethylammonium O,O’-dialkhyldithiophosphates （DDP）, byreaction of phosphorus pentasulfide, alcohol （or phenol） with diethylamine, and11complexes and24ternary complexes contain tetraazamacycrolic or nitrogenbase ligangs were synthesized in this paper. The N,N-diethylammoniumO,O’-dialkhyldithiophosphates and their complexes were characterized byelemental analysis, IR spectra, UV-vis spectra,1HNMR spectra andthermogravimetry analysis, and the seven single-crystal structure weredetermined by X-ray single-crystal diffraction, which are（4-MeC₆H₄O）₂PS₂^NH₂Et₂（I-6）, Ni[S₂P（OC₆H₄Bu-t-4）₂]₂（Ⅲ-1）,Pb[S₂P（OC₆H₄Bu-t-4）₂]₂（Ⅲ-5）, Bi[S₂P（OC₆H₄Bu-t-4）₂]3（Ⅲ-7）,{Ni（hmtade）[S₂P（OC₆H₄Bu-t-4）₂]₂}（IV-1）,{Ni（dmdpde）[S₂P（OC₆H₄Me-4）₂]₂}（IV-11）,and {Pb[S₂P（OC₆H₄Bu-t-4）₂]₂·Py2}（V-6）（the ligand hmtade is5,7,7,12,14,14-hexamethyl-1,4,8,11-tetrazacyclotetradeca-4,11-diene; and the ligand dmdpde is5,12-dimethyl-7,14-diphenyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene）.The crystal structure analysis show that there are two independent subunitsin the asymmetric structure unit of the compound I-6, and one-dimensionalnetwork structure is formed by intermolecular N-H···S hydrogen bonds betweenthe subunits; In the complex Ⅲ-1, the nickel（Ⅱ） ion is coordinated by four sulfuratoms of the ligand （4-t-BuC₆H₄O）₂PS₂^-and form a square planar configurationNiS4. A one-dimensional network structure is formed by meanth of C-H···Shydrogen bonds and S…S short contracts in the crystal structure of the complexⅢ-1; In the complex Ⅲ-5, the complex is binuclear one and contains two chelating anisobidentate and two bridging tridentate （4-t-BuC₆H₄O）₂PS₂^-ligands.Each Pb（Ⅱ） ion is in a distorted ψ-pentagonal bipyramidal geometry by fivesulfur atoms from three （4-t-BuC₆H₄O）₂PS₂^-ligands, a aryl group of one ofbridging （4-t-BuC₆H₄O）₂PS₂^-ligand, and a lone pair of stereochemically activeelectrons originating from the Pb（Ⅱ） ion. The two bridging ligands（4-t-BuC₆H₄O）₂PS₂^-each bridge two lead atoms to form an chair conformation ofeight-membered ring [Pb₂S₄P₂]; In the complex Ⅲ-7, the bismuth（Ⅲ） ioncoordinates with six sulfur atoms from three molecules of （4-t-BuC₆H₄O）₂PS₂^-,bismuth（Ⅲ） ion locate at the corners of the distorted octagonal. The C3-H3…O3hydrogen bond lead the complex to form a one-dimensional network structure inthe structure of Ⅲ-7; In the complex IV-1, the nickel（Ⅱ） ion is coordinated byfour nitrogen atoms from hmtade ligang and two sulfur atoms from two（4-t-BuC₆H₄O）₂PS₂^-ligands forming a distorted octagonal, and there is aintermolecular N-H···S hydrogen bond between the hmtade ligand and（4-t-BuC₆H₄O）₂PS₂^-; In the complex IV-11, that crystal structure is analogous tothe crystal structure of complex IV-1, but there are two intramolecular N-H···Shydrogen bonds in this molecules; In the complex V-6, which is binuclearcomplex and contains two chelating anisobidentate and two bridging tridentate（4-t-BuC₆H₄O）₂PS₂^-ligands. Each lead（Ⅱ） ion is coordinated by two nitrogenatoms from two molecules pyridine and five sulfur atoms from（4-t-BuC₆H₄O）₂PS₂^-ligand forming a distorted pentagonal bipyramidal geometry,and the two bridging ligands （4-t-BuC₆H₄O）₂PS₂^-each bridge two lead（Ⅱ） ion toform an chair conformation of eight-membered ring [Pb₂S₄P₂].The corrosion inhibition of the compounds (C₆H₁₁O)₂PS₂NH₂Et₂（I-1）,（PhO）₂PS₂NH₂Et₂（I-2）,（PhCH₂O）₂PS₂NH₂Et₂（I-3）, and（PhCH₂CH₂O）₂PS₂NH₂Et₂（I-4） against the corrosion of Q235steel in acidsolution were studied by weight loss measurements, electrochemicalmeasurements, AFM, and SEM techniques. The effects of corrosion inhibitorconcentration, temperature, acid concentration and time were studied. The studiesshow that all the corrosion inhibitor act as good inhibitor for the corrosion ofQ235steel in acid solution. They are all mixed-type inhibitor. The adsorption of all inhibitors obey Langmuir adsorption isotherm. The chemisorption takes placespontaneously by inhibitors I-1, I-3, and I-4molecules on Q235steel surface.The behavior adsorption of inhibitor I-4on the Q235steel surface isphysisorption.