J. Seetharamappa

Abstract: The synthesis and structure elucidation of the dimeric form of molybdenum(IV) oxo-complexes with N-alkylphenothiazines as ligands have been studied. These complexes were identified by IR and electronic spectra, magnetic susceptibility, DTA, TGA, conductometric and analytical data. These results permit us to assign the formula Mo2O4(L)2(H2O)2 (where L = N-alkylphenothiazine). Some interactions of these complexes with biologically important compounds like L -cysteine and histidine and potential ligands such as 1,10-phenanthroline and 2,2′-bipyridyl have been reported.

Abstract: A new series of lanthanide(III) nitrate complexes of 10-(2-dimethylaminopropyl)phenothiazine (promethazine or PM) with the general formula [Ln(PM)2(NO3)2]NO3, where Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, have been prepared and characterized based on elemental analysis, molar conductivity, magnetic susceptibility, spectroscopic data, and thermal studies Conductance study indicates a 1:1 ionic ratio for the complexes in solution The infrared spectra show that promethazine acts as a bidentate ligand using the heterocyclic nitrogen atom and tertiary nitrogen atom of the side chain as the sites of coordination Only two of the nitrate ions are coordinated bidentately to the central metal ion while another nitrate ion remains outside the coordination sphere A tentative structure has been proposed for the complexes

Abstract: The synthesis and reactivity of new lanthanocene complexes incorporating phenothiazine ligand are described. The reaction of phenothiazine (HPtz) with nBuLi in THF and subsequently with 1 equiv. of (C5H5)2LnCl(THF) gave the original complexes (C5H5)2LnPtz(THF) (Ln = Yb(1), Er(2), Dy(3), Y(4)). Treatment of complexes 1–4 with N,N′-diisopropylcarbodiimide results in mono-insertion of carbodiimide into the Ln–N(Ptz)-bond to yield the corresponding guanidinates (C5H5)2Ln[(iPrN)2C(Ptz)] (Ln = Yb (5), Er (6), Dy (7), Y(8)). Further investigations indicate that phenyl isothiocyanate react with complexes 1 and 4, giving the correspondent insertion products (C5H5)2Ln[SC(Ptz)NPh](THF) (Ln = Yb(9), Y(10)). All these complexes were characterized by elemental analysis and spectroscopic properties. The structures of complexes 2, 5 and 9 were also determined by the X-ray single crystal diffraction analysis. All these reactions provide a new strategy for introducing a functional substituent at the nitrogen atom of phenothiazine via forming a new C–N(ring) bond.

Abstract: FT-IR and FT-Raman spectra of 1H-2,2-dimethyl-3H-phenothiazin-4[10H]-one were recorded and analyzed. The vibrational wavenumbers were computed using HF/6-31G(d) and B3LYP/6-31G(d) basis. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands obtained in infrared and Raman spectroscopies of the studied molecule. The first hyperpolarizability, infrared intensities and Raman activities are reported. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The geometrical parameters of the title compound are in agreement with XRD crystal structure data. The red shift of the N H stretching wavenumber in the infrared spectrum from the computed wavenumber indicates the weakening of the N H bond.

Abstract: FT-IR and FT-Raman spectra of 1-(5,5-dioxido-10H-phenothiazin-10-yl)ethanone were recorded and analyzed. The vibrational wavenumbers were computed using B3LYP/6-31G∗ and SDD basis. Potential energy distribution of normal modes of vibrations was done using GAR2PED program. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. The stability of the molecule arising from hyper conjugative interaction and charge delocalization has been analyzed using NBO analysis. Molecular electrostatic potential was performed by the DFT method and infrared intensities and Raman activities are also reported. MEP shows that the negative potential sites are on oxygen atoms and the positive potential sites are around the nitrogen atoms. The geometrical parameters of the title compound (SDD) are in agreement with XRD crystal structure data. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of nonlinear optics.

Abstract: Polynuclear complexes of RHII and RHIII with fiveN-alkylphenothiazines as principal ligands have been prepared. The complexes were characterized by their elemental analyses, molar conductivities, and spectral data. The molecular formulae of the new complexes are as follows: [Rh3(PTZ)2(OH2)2Cl8]Cl, where PTZ=chlorpromazine or promethazine; [Rh3(EP)2(OH2)2Cl8][Rh(OH2)2Cl4], where EP=ethopropazine; [Rh4(TF)2(OH2)5Cl9]Cl·H2O, where TF=trifluoperazine; and [Rh2(TC)3(OH2)Cl6]. H2O, where TC=2-chlorophenothiazine. A tentative structure for each of the complexes is proposed.