@article { ISI:000351969900008, title = {First naphthosemiquinone complex of K+ with vitamin K3 analog: experiment and density functional theory}, journal = {Journal of Molecular Structure}, volume = {1088}, year = {2015}, month = {MAY}, pages = {56-63}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Synthesis and characterization of potassium complex of 2-hydroxy-3-methyl-1,4-naphthoquinone (phthiocol), the vitamin K3 analog, has been carried out using FT-IR, UV-Vis, H-1 and C-13 NMR, EPR, cyclic voltammetry and single crystal X-ray diffraction experiments combined with the density functional theory. It has been observed that naphthosemiquinone binds to two K+ ions extending the polymeric chain through bridging oxygens O(2) and O(3). The crystal network possesses hydrogen bonding interactions from coordinated water molecules showing water channels along the c-axis. C-13 NMR spectra revealed that the complexation of phthiocol with potassium ion engenders deshielding of C(2) signals, which appear at delta = similar to 14.6 ppm whereas those of C(3) exhibit up-field signals near delta similar to 6.9 ppm. These inferences are supported by the M06-2x based density functional theory. Electrochemical experiments further suggest that reduction of naphthosemiquinone results in only a cathodic peak from catechol. A triplet state arising from interactions between neighboring phthiocol anion lead to a half field signal at g = 4.1 in the polycrystalline X-band EPR spectra at 133 K. (C) 2015 Elsevier B.V. All rights reserved.

}, keywords = {C-13 NMR, DFT, hydrogen bonding, Naphthosemiquinone, Phthiocol, Vitamin K3}, issn = {0022-2860}, doi = {10.1016/j.molstruc.2015.01.053}, author = {Kathawate, Laxmi and Gejji, Shridhar P. and Yeole, Sachin D. and Verma, Prakash L. and Puranik, Vedavati G. and Salunke-Gawali, Sunita} } @article {47464, title = {Reactions of 2,3-dibromonaphthalene-1,4-dione and pyridyl amines: X-ray structures, DFT investigations, and selective detection of the Hg2+ and Ni2+ ions}, journal = {Engineered Science}, volume = {14}, year = {2021}, month = {FEB}, pages = {78-93}, type = {Article}, abstract = {

In this work, the products formed by the reaction between 2,3-dibromonaphthalene-1,4-dione with (pyridine-2-yl)methanamine and (pyridine-4-yl)methanamine are discussed in detial. The products 2-amino-3-bromonaphthalene-1,4-dione (A) and 2-aminonaphthalene-1,4-dione (B(1)) obtained are characterized through\ 1H and\ 13C-NMR, FTIR, mass spectrometry, single-crystal X-ray diffraction experiments, which are in conjunction with wB97X based density functional theory.\ compound\ A\ can effectively and selectively detect Hg2+\ and Ni2+\ ions, and proposes a potential mechanism of action.

}, issn = {2576-9898}, doi = {10.30919/es8d427}, author = {Aggrwal, Gunjan and Salunke-Gawali, Sunita and Gejji, Shridhar P. and Nikalje, Milind and Chakravarty, Debamitra and Verma, Prakash L. and Gosavi-Mirkute, Prajkta and Harihar, Shital and Jadhav , Mahesh and Puranik, Vedavati G.} }