Reactions of arenes and heteroarenes with aromatic aldehydes proceeded smoothly in the presence of a catalytic combination of [Ir(COD)Cl]2-SnCl4 to afford the corresponding triarylmethane derivatives (TRAMs) in high yields. This 100% TRAM selective transformation is clean and eliminates the use of acid systems.

The selenodecarboxylation of phenylpropiolic and cinnamic acid derivatives with diorgano diselenide is promoted by iodosobenzene diacetate (PhI(OAc)2, IBDA) in acetonitrile at 30−60 °C, leading to the formation of alkynyl selenides and vinyl selenides in moderate to excellent yields. Similar reactivity is also shown by iodosylbenzene (PhIO, IB). The reaction is also triggered in the solid state. An electrophilic mechanism is proposed for the transformation.

Organic molecules with tunable fluorescence quantum yield are attractive for opto-electronic applications. A fluorophore with tunable fluorescence quantum yield should be a better choice for a variety of applications that...

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A new easy-to-synthesize chemosensor, 3,3'-bis(indolyl)-4-chlorophenylmethane (hereafter S), was designed, synthesized and employed as a selective optical chemosensor for fluoride ions.(1)H NMR and density functional studies on the system have been carried out to determine the nature of the interaction between S and X(-) (X = inorganic anions) responsible for the significant fluoride-induced changes in the absorption properties of S. The experimental results reveal that abstraction of an acidic proton of S by the fluoride ion, leading to the formation of anionic species, is responsible for the spectral changes. These changes allow signaling for the fluoride ion to detect and estimate the concentration of fluoride ion present even at the submicromolar level, accurate up to 2 μM. Calculations of the transition energies of S, S(-), and S···F(-) (hydrogen bonded complex) show that only S(-) is responsible for the long-wavelength absorption band in the presence of F(-).

IEEE 802.15.4-2003 is a standard for Low rate, Low node being the only node that has no other node above it in the powered, Low memory wireless personal area network hierarchythe hierarchy of the tree is symmetrical[2], each (WPAN).The Physical layer (PHY) and Medium access control node in the network having a specific fixed number, f, of (MAC) specification has been given by IEEE [12, l1]and the nodes connected to it at the next lower level in the hierarchy, Network layer by ZigBee Alliance [17]. They support two kind of the number, f, being referred to as the 'branching factor' of the

Heterogeneous green catalysis by using magnetically separable nanometal–oxide catalysts has become a subject of prime focus recently. PXRD (powder X-ray diffraction), FESEM (field emission scanning electron microscopy), and HRTEM (high-resolution tunneling electron microscopy) with IR and Raman spectroscopy are applied to analyze the structural and microstructural properties of nanosized (∼15.3 nm) CuFe 2 O 4 synthesized by both sonochemical and mechanochemical processes. The sonochemical process provides a better uniformity of sizes of the nanoparticles (NPs). Rietveld refinement with the PXRD pattern reveals the inverse spinel-like architecture of CuFe 2 O 4 NPs. The Raman spectra also indicate the phase purity of the synthesized material. The static magnetic measurements are performed at different magnetic fields and temperature ranges from 300 to 5 K, which confirms the existence of the ferrimagnetic phase mixed with some finer superparamagnetic (SPM) nanophases within the sample. Unsaturated magnetization is observed even at an applied 5 T magnetic field for the presence of spin-canting nature in the partially inverted copper ferrite phases at the surfaces of the nanoparticles. Now, these coupled magnetic CuFe 2 O 4 NPs are used as a heterogeneous catalyst for three-component Huisgen 1,3-dipolar cycloaddition click reaction in aqueous media. By this catalyst system, we were able to couple alkyl halide, epoxide, or boronic acid with alkynes efficiently to furnish 1,4-disubstituted 1,2,3-triazoles in excellent yields within very short reaction time. The test for heterogeneity, reusability, and reproducibility of the catalyst has also been performed successfully without prominent decrease in yield up to the fifth cycle.