Dibenzyl sulfoxide [C6H5CH2)2SO, DBzSO] has been studied using density functional theory (DFT) methods with a particular emphasis on the theoretical 1H-NMR spectra of the methylene protons. The 1H-NMR chemical shifts of the methylene protons of DBzSO can be divided into two main types. Four possible structures of DBzSO were considered and the total energies were calculated for both a vacuum and in CDCl3 solvent. The change of length of S-O and S-C bonds in solvent was more obvious than that of the C(CH2)-C(C6H5) bonds; The S-O bond was longer and S-C bond was shorter in CDCl3. The essence effect of solvent on the properties of dibenzyl sulfoxide should come from the change of the geometrical structure. The change of shift Δx, [shift (solvent) - shift (vacuum)] showed that the effect of solvent on methylene protons of dibenzyl sulfoxide was apparent. Except of the other H of the rings, the two ortho H which were near S-O bond appeared more sensitivity on the solvent. The optimized structures in CDCl3 were in good agreement with the experimental data. The NMR peaks of methylene protons should be split more apparently in actual circumstance and the complex split of CH2 1HNMR peaks should be explained in some degree.

The thermodynamics properties of synthesize reactions of Ph3SnR (R= N (C4H4), N(C8H6), C6H5) and CpM(CO)2CY(M=Cr, Mn; Y=S, Se), the total energy and Mulliken atomic charges of the compound products M(CO)2CY-Ph3XR(M=Cr, Mn; X=Sn, Ge; Y=S, Se; R= N(C4H4), N(C8H6), C6H5) with different substitute positions on the benzene ring were investigated using DFT method. The calculation results of total energy showed that the ligand was determinant of the favourable substituted position and the central metal of two different type ligands CpCr(CO)2CY(Y=S, Se) and CpMn(CO)2 CY(Y=S, Se) was the key factor; whether the reactants Ph3SnR( R= N(C4H4), N(C8H6)) and Ph3SnR( R= C6H5) had the pyrrole or not had effect on the character of substituted position. The Mulliken atomic charges of central metal Sn and Ge showed that the atom charge value of Sn and Ge of M(CO)2CY-Ph4X was smaller than M(CO)2CY-Ph3XN (C4H4) and M(CO)2CY-Ph3XN(C8H6) (M=Cr, Mn; X=Sn, Ge; Y=S, Se) correspondingly; electron-donating trend of Ph3GeR group was stronger than that of Ph3SnR group; the pyrrole group had some conjugation effects which made the electronic distribute more even. The calculation results of thermodynamics properties of the synthesize reactions of Ph3SnR(R=N(C4H4), N(C8H6), C6H5) and CpCr(CO)CS showed that the reaction possibility was small at the general condition; ligand CpMn(CO)2CY(Y=S, Se) was more favorable to the reaction than CpCr(CO)2CY(Y=S, Se); different substituted positions would have effect on the reaction possibility apparently. Decreasing temperature would be favorable to the possibility of the reactions, but increasing temperature might be favourable to the rate of reactions.

Mixed-ligand Pt(II) complexes containing pyrazine (C4N2H4, pz) and dibenzyl sulfoxide [C6H5CH2)2SO, DBzSO] ligands have been studied using density functional theory (DFT) methods with a particular emphasis on the theoretical1H-NMR spectra of the methylene protons. The DFT optimization calculations on Pt(DBzSO)Cl2(pz) and {Pt(DBzSO)Cl2}2(pz) predicted the structure parameters, vibrational frequency and1H-NMR spectra. Different structures of DBzSO will affect the bond lengths and angles in the complexes, except for the pz ligands. The [shift(Pt(II)complex)-shift(sulfoxide)] values of trans-Pt(DBzSO)(pz)Cl2were smaller than those for cis-Pt(DBzSO)(pz)Cl2and the calculation results appear to be reasonable. The1H-NMR spectra of the methylene protons of cis- and trans-{Pt(DBzSO)Cl2}2(pz) indicate that these two structures have high symmetry.