Highly Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles in the Presence of Diazabicycloundecene

New highly efficient method for the cyclization of acylamidoximes in the presence of diazabicycloundecene was developed and incorporated into a general and practical one‐pot synthesis of 1,2,4‐oxadiazoles (11 examples, 85–97% yields).     

Non-isothermal degradation kinetics of PLA-functionalized gum (fG) biocomposite with dicumyl peroxide (DCP)

Journal of Thermal Analysis and Calorimetry - In the present investigation, gene expression programming (GEP) is used to predict thermal conductivity of nanofluids consisting of $$\hbox {Al}_2\hbox...     

Phosphorylated chitin as a chemically modified polymer for ecofriendly corrosion inhibition of copper in aqueous chloride environment

Research on Chemical Intermediates - Heterocyclic organic molecules containing oxygen, nitrogen or sulfur are generally used as inhibitors for corrosion protection of copper. These compounds form...     

Dimethylaminoalkyl chalcogenolate palladium(II) complexes as an efficient copper- and phosphine-free catalyst for Sonogashira reaction

N,N-Dimethylaminoalkyl chalcogenolate Pd(II) complexes [PdCl(E^∩NMe₂)]_n has been investigated as a moisture/air-stable and robust catalyst for Sonogashira cross-coupling reaction in the absence of copper and phosphine ligand. The dimeric palladium(II) complex of selenium containing ligand shows the best catalytic activity as compared with monomeric and trimeric complexes. The variety of functional groups are tolerated under optimized catalytic systems and provide excellent yields of the products.     

Investigations on Pd:SnO2/porous silicon structures for sensing LPG and NO2 gas

P-type porous silicon (PS) structure has been prepared by anodic electrochemical etching process under optimized conditions. Photoluminescence studies of the PS structure show emission at longer wavelengths (red) for the excitation at 365 nm. Scanning electron microscope investigations of the PS surface confirm the formation of uniform porous structure, and the pore diameter have been estimated as 25 μm. Pd:SnO₂/PS/p-Si heterojunction with top gold ohmic contact developed by conventional methods has been used as the sensor device. Sensing properties of the device towards liquefied petroleum gas (LPG) and NO₂ gas have been investigated in an indigenously developed sensor test rig. The response and recovery characteristics of the sensor device at different operating temperatures show short response time for LPG. From the studies, maximum sensitivity and optimum operating temperature of the device towards LPG and NO₂ gas sensing has been estimated as 69% at 180 °C and 52% at 220 °C, respectively. The developed sensor device shows a short response time of 25 and 57 s for sensing LPG and NO₂ gases, respectively. Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006.     

Multinuclear complexes containing [Pt2(μ-S)2(Ptolyl3)4] as a metallo-ligand

Treatment of [PtCl₂(Ptolyl₃)₂] (tolyl = 4-MeC₆H₄) with Na₂S in benzene gave [Pt₂(μ₂-S)₂(Ptolyl₃)₄] (1), which is soluble in common organic solvents. Reactions of (1) with various metal complexes have been studied and several polynuclear metal aggregates isolated. These new complexes were characterized by elemental analysis and n.m.r. spectroscopy. This revised version was published online in June 2006 with corrections to the Cover Date.     

Synthesis, structures and spectroscopic properties of cyclometalated tri-tert-butylphosphine complexes of platinum(II)

Reactions of [Pt₂(μ-Cl)₂(C^∩P)₂] (C^∩P = CH₂C(Me₂)PBu^t₂-C,P) with various anionic ligands differing in ligand bite and denticity have been investigated and the resulting products have been characterized by elemental analyses and NMR (¹H, ¹³C, ³¹P, ¹⁹⁵Pt) spectroscopy. Stereochemistry of the complexes has been deduced by NMR spectroscopy. Structures of [Pt₂(μ-SPh)₂(C^∩P)₂], [Pt₂(μ-pz)₂(C^∩P)₂], [PtCl(Spy)(PBu^t₃)], [Pt₂(μ-SCOPh)₂(C^∩P)₂] and [Pt{S₂P(OPrⁱ)₂}(C^∩P)] have been established by single crystal X-ray diffraction analyses. The complex [Pt₂(μ-SPh)₂(C^∩P)₂] adopts a sym cis configuration while other binuclear complexes exist in a sym trans configuration. The molecular structure of [Pt{S₂P(OPrⁱ)₂}(C^∩P)] revealed that complex comprises of two four-membered chelate rings but in solution a dimeric structure based on ¹⁹⁵Pt NMR data has been suggested.     

The chemistry of tri- and high-nuclearity palladium(II) and platinum(II) complexes

This review gives an overview of the progress on tri- and high-nuclearity palladium(II) platinum(II) complexes and discusses recent developments in the chemistry of these complexes. Three or more square-planar metal atoms can be assembled in several ways resulting into myriad geometric forms of the resulting complexes. These square planes may be sharing a corner, an edge and two edges or even separated by ligands having their donor atoms incapable of forming chelates yielding dendrimers and self-assembled molecules. A variety of ligands have been used to stabilize these complexes. The chemistry of these complexes has been dealt based on nuclearity of the complexes. Synthetic, spectroscopic, structural aspects and applications of these complexes are described in this review.     

LMI approach to the global robust stability of a larger class of neural networks with delay

Sufficient conditions in the form of linear matrix inequality for the uniqueness and global asymptotic stability of the equilibrium point of a large class of uncertain neural networks with delay are presented. The conditions are based on norm-bounded uncertainties. An example is given to show the effectiveness of the obtained results. A comparison is made between the present approach and an earlier approach due to Lu, Rong and Chen. An error is corrected in an earlier publication.