Synthesis of 2-arylpropionic acids by electrocarboxylation of benzylchlorides catalysed by PdCl2(PPh3)2

Electrochemical carboxylation of benzylchlorides catalysed by Pd(II) complex afforded 2-arylpropionic acids in good yields under atmospheric pressure of carbon dioxide at constant current of 10 mA cm⁻². Mechanistic and electrochemical studies revealed the cooperative role of reduced palladium species in the activation of carbon dioxide.     

Genetic oscillation patterns

We apply symbolic dynamics to analyze dynamical measurements obtained from gene regulations of cells. Dividing the temporal signals of for instance protein concentrations into regimes of monotonic increasing or decreasing levels gives a natural symbolic division which can be applied to guess the underlying negative feed-back loops. We further study how negative feed-back loops can be placed on a hexagonal lattice and investigate the dynamical consequences of that.     

Neutron diffraction studies on La2−x Dy x Ca2xBa2Cu4+2x Oz superconductors

Structural studies on Dy-substituted La-2125 type superconductors have been carried out by neutron diffraction experiments at room temperature using a monochromatic neutron beam of wavelength (λ) = 1.249 Å. A series of samples with La_2-xDy_xCa_2xBa₂Cu_4+2xO_z stoichiometric composition, forx = 0.1–0.5, have been studied for their structural properties. A tetragonal Y-123 unit cell was taken as the starting model for the Rietveld analysis. All the samples fit into the starting model, with no structural transition taking place with increasing dopant concentration. The results of Rietveld analysis and structural properties will be discussed in detail.

     

Some physical solutions of Yang’s equations forSU(2) gauge fields, Charap’s equations for pion dynamics and their combination

Some previously obtained physical solutions [1–3] of Yang’s equations forSU(2) gauge fields [4], Charap’s equations for pion dynamics [5,6] and their combination as proposed by Chakraborty and Chanda [1] have been presented. They represent different physical characteristics, e.g. spreading wave with solitary profile which tends to zero as time tends to infinity, spreading wave packets, solitary wave with oscillatory profile, localised wave with solitary profile which becomes plane wave periodically, and, wave packets which are oscillatory in nature.     

New criteria to identify spectrum

In this paper we give some new criteria for identifying the components of a probability measure, in its Lebesgue decomposition. This enables us to give new criteria to identify spectral types of self-adjoint operators on Hilbert spaces, especially those of interest.     

An efficient approach towards the stereospecific synthesis of epoxides from phospholene oxides

A novel method has been developed for stereospecific conversion of 2-phospholene 1-oxides into their corresponding 2,3-epoxides in high yields using sodium peroxide as a reagent.     

An efficient regioselective copper catalyzed multi-component synthesis of 1,3-disubstituted pyrazoles

An efficient synthesis of unsymmetrically substituted 1,3-pyrazole derivatives has been developed via three-component coupling reaction involving 3-(dimethylamino)-1-phenylprop-2-en-1-one, hydrazine, and aryl halides in one pot process exhibiting high regioselectivity. The pyrazole synthesis proceeds via a sequential series of reactions such as Michael addition, heterocyclization, dehydration, and Ullmann cross-coupling.     

First Diastereoselective PasseriniSmiles and UgiSmiles Reactions Using Chiral Aldehydes

A diastereoselective O/N‐arylative Passerini/Ugi reaction of chiral aldehydes with commercially available isocyanides affording O‐aryl amides and N‐aryl amides, respectively, as products in moderate to good yields, together with de values, is reported.