Kannan Thirumurthy

Fly-ash:H2SO4 catalyzed solvent free efficient synthesis of some aryl chalcones under microwave irradiation

Some 2E aryl chalcones have been synthesized using greener catalyst Fly-ash:H(2)SO(4) assisted solvent free environmentally benign Crossed-Aldol reaction. The yields of chalcones are more than 90%. The synthesized chalcones are characterized by their physical constants and spectral data.

Solvent-free synthesis, spectral correlations and antimicrobial activities of some aryl imines.

A series of aryl imines have been synthesized by Fly-ash: H2SO4 catalyzed microwave assisted process under solvent-free conditions. The yields of the imines have been found to be more than 87%. The purity of all imines has been checked using their physical constants and spectral data as published earlier in literature. The UV λmaxCN(nm), infrared νCN(cm(-1)), NMR δ(ppm) of CH and CN spectral data have been correlated with Hammett substituent constants and F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the above spectral data has been studied. The antimicrobial activities of All synthesised imines have been studied using Bauer-Kirby method.

Eco-friendly synthesis and antimicrobial activities of some 1-phenyl-3(5-bromothiophen-2-yl)-5-(substituted phenyl)-2-pyrazolines

Background Green catalyst fly ash: H2SO4 was prepared by mixing fly ash and sulphuric acid. Microwave irradiations are applied for solid phase cyclization of 5-bromo-2-thienyl chalcones and phenyl hydrazine hydrate in the presence of fly ash: H2SO4 yields, 1-phenyl-3(5-bromothiophen-2-yl)-5-(substituted phenyl)-2-pyrazolines. These pyrazolines were characterized by their physical constants and spectral data. The antimicrobial activities of all synthesized pyrazolines have been studied. Results Scanning electron microscopy (SEM) analysis shows the morphology changes between fly ash and the catalyst fly ash: H2SO4. The SEM photographs with the scale of 1 and 50 μm show the fly-ash particle is corroded by H2SO4 (indicated by arrow mark), and this may be due to dissolution of fly ash by H2SO4. The yields of 1-phenyl-3(5-bromothiophen-2-yl)-5-(substituted phenyl)-2-pyrazolines is more than 75% using this catalyst under microwave heating. All pyrazolines showed moderate activities against antimicrobial strains. Conclusion We have developed an efficient catalytic method for synthesis of 1-phenyl-3(5-bromothiophen-2-yl)-5-(substituted phenyl)-2-pyrazolines by solid phase cyclization using a solvent-free environmentally greener catalyst fly ash: H2SO4 under microwave irradiation between aryl chalcones and hydrazine hydrate. This reaction protocol offers a simple, economical, environment friendly, non-hazardous, easier work-up procedure, and good yields. All synthesized pyrazoline derivatives showed moderate antimicrobial activities against bacterial and fungal strains.

A facilely designed, highly efficient green synthetic strategy of a peony flower-like SO42−–SnO2-fly ash nano-catalyst for the three component synthesis of a serendipitous product with dimedone in water

For the first time we have successfully found a serendipitous product 2-((2-((9-ethyl-9H-carbazol-3-yl)amino)-4,4-dimethyl-6-oxocyclohex-1-en-1-yl)(phenyl)methyl)-5,5-dimethylcyclohexane-1,3-dione and its derivatives by utilizing a SO42−–SnO2-fly ash nano-catalyst in water. We have designed a SO42−–SnO2-fly ash nano-catalyst which is easily separable, has good catalytic activity, good reusability and notable industrial applications. The catalytic role of Sn–O involves its high affinity with the carbonyl group of dimedone. The major component of fly ash (SiO2) may enhance the catalytic activity of oxidation processes. With these properties, the conversion of product could be rapid and high yielding. The facilely designed, SO42−–SnO2-fly ash nano-catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), confocal Raman spectroscopy, powder X-ray diffraction (PXRD), field emission electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS and elemental color mapping), high resolution transmission electron microscopy (HR-TEM) and UV-Visible diffuse reflectance spectroscopy (UV-Vis DRS) techniques. The nano-cube and peony flower like morphologies were found in the FE-SEM and HR-TEM images. The flower like SO42−–SnO2-fly ash catalyst’s highly stable nature is favorable for organic reactions. The crystalline nature, surface morphology, chemical composition and morphology of the reused SO42−–SnO2-fly ash nano-catalyst were proved by PXRD, FE-SEM, EDAX and HR-TEM analyses respectively. The facilely designed SO42−–SnO2-fly ash nano-catalyst is versatile from both environmental and economical points of view. The synthesized serendipitous product derivatives and byproducts were characterized by FT-IR, nuclear magnetic resonance (NMR) and high resolution-mass spectrometry (HR-MS).

Crystal structure of (E)-N-(3,3-di-phenyl-allyl-idene)-9-ethyl-9H-carbazol-3-amine.

In the title compound, the carbazole ring system is essentially planar (maximum deviation = 0.025 Å). The crystal packing is stabilized by intermolecular C—H⋯π interactions, forming a three-dimensional supramolecular network.

Crystal structure of (E)-N-[(2-chloro-6-meth-oxy-quinolin-3-yl)methyl-idene]-9-ethyl-9H-carbazol-3-amine.

In the title compound, C25H20ClN3O, the dihedral between the carbazole and quinoline ring systems is 50.2 (1)°. The crystal packing features C—H⋯π and π—π interactions, which generate a three-dimensional network.

Synthesis, Characterization and Synthetic Applications of Fly-ash:H3PO4 Nanocatalyst

Abstract The solid acidic nanocatalyst fly-ash:H3PO4 was prepared and characterized by FT-IR, SEM, EDS and TEM analysis. This catalyst was utilized for aldol condensation, coupling and cyclization reaction. The effect of catalytic activity of this fly-ash:H3PO4 nanocatalyst was studied with the obtained yield of products under solvent-free conditions. In this synthetic reaction the obtained yields were more than 95 %.

Perchloric acid catalyzed condensation of amine and aldehydes: Synthesis and antibacterial activities of some aryl (E)-imines

Abstract A series of Schiff’s bases (aryl E-imines) have been derived from the perchloric acid catalyzed condensation of aryl amines and substituted benzaldehydes. The yield of the Schiff’s bases are more than 80%. The synthesized Schiff’s bases are characterized by their physical constants, analytical and spectroscopical data. The antibacterial activities of these Schiff’s bases have been studied using Bauer-Kirby method.

SOLID FLY-ASH:H2SO4 CATALYZED MICROWAVE ASSISTED SOLVENT-FREE CONDENSATION:SYNTHESIS OF SOME TRIFLUOROMETHYL-IMINES

ABSTRACT Good yield of trifluoromethyl-imines have been synthesized by Fly-ash:H 2 SO 4 catalyzed condensation of anilines and phenyl trifluoromethyl ketone in mi-crowave irradiation under solvent free conditions. Keywords: Fly-ash:H 2 SO 4, Greener synthesis, Trifluoromethylimines, Anilines. e-mail: drgtnarayanan@gmail.com INTRODUCTION Chiral imine derivatives possess multipronged biological activities such as antimicrobial 1 , anticancer 2 , antiplasmodic-antihypoxic 3 , antitubularcular 4 , nematicidal, insecticidal1e 5 , anti-inflammatory, and lipoxygenase 6 . The imine moieties are important intermediate and versatile starting materials for synthe-sis of chiral amines 7-13 pyrimidine derivatives, phenylhydrazones, azomethines, indoles, quinoxalines, imidazoles, by hydrogenation 14 , nucleophilic addition with organometallics 15 and cycloaddition reaction 16 . The unique condensation of carbonyl compounds with amines is a well-known reaction. Many reagents 17 was obtained on evaporation of solvent. The solid, on recrystallization with were used for synthesis of optically active imines such as Lewis acids, mo-lecular sieves in ionic liquids, infrared