New polymeric, dimeric and mononuclear dioxidomolybdenum(vi) complexes with an ONO donor ligand: crystal structures, DFT calculations, catalytic performance and protein binding study of the ligand. (3rd May 2017)

• Record Type: Journal Article
• Authors: Biswal, Debanjana; Pramanik, Nikhil Ranjan; Chakrabarti, Syamal; Drew, Michael G. B.; Sarkar, Bithika; Maurya, Mannar R.; Mukherjee, Sanjib K.; Chowdhury, Pramit
• Is Part Of: New journal of chemistry. Volume 41:Number 10(2017)
• Page Start: 4116
• Page End: 4137
• Publication Date: 2017-05-03
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj00136c
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Catalytic activity and BSA binding is reported. Abstract : Reaction of [MoO2 (acac)2 ] with a new ONO donor Schiff base ligand (H2 L), derived from 2-aminobenzoylhydrazide and benzoyl acetone in methanol under refluxing conditions, yields polymeric [MoO2 L] n (1 ) and dimeric [MoO2 L]2 ·THF (2 ) dioxidomolybdenum(vi ) complexes. Complexes1 and2 undergo reaction with monodentate Lewis bases forming mononuclear complexes [MoO2 L(3-pic)] (3 ), [MoO2 L(1-allylimz)] (4 ) and [MoO2 L(DMSO)] (5 ). In these complexes, the ligand is coordinated to the cis -[MoO2 ] 2+ cores through enolic oxygens and an azomethine nitrogen. In complexes3 and4 the remaining sixth coordination site is occupied by the nitrogen atoms and in complex5 by the oxygen atom of the Lewis base. The crystal structures of these complexes (1–5 ) have been determined by single crystal X-ray diffraction. The molybdenum atom exhibits a distorted octahedral coordination sphere. In complex1, a 1D zigzag polymeric chain is formed through OMo–O interactions. In complex2, a centrosymmetric dimer is formed through weak interaction of the non-coordinating amine nitrogen with the molybdenum centre. In contrast complexes3, 4 and5 are monomeric. The investigated complexes have also been characterized by elemental analysis, various spectroscopic techniques, thermogravimetric analysis and cyclic voltammetry. Supportive DFT calculations on the complexes have been carried out. The dioxidomolybdenum(vi ) complexes have been tested for catalytic epoxidation and oxidative bromination of styrene. Fluorescence spectral measurements carried out by varying the concentration of the ligand indicate strong fluorescence resonance energy transfer (FRET) from BSA to the ligand and from the binding studies it is revealed that BSA has two binding sites for the ligand.