A Facile Transfer of Dicyano Methylene Group Between Arylidenemalononitrile and Aldehyde

Arylidenemalononitrile undergoes facile exchange of dicyano methylene group with β-formyl steroidal enamide as well as aromatic aldehydes under mild base catalysed reaction.     

An efficient and reusable vanadium based catalytic system for room temperature oxidation of alcohols to aldehydes and ketones

A simple and efficient vanadium based catalyst system for the oxidation of primary and secondary alcohols to aldehydes or ketones is reported using tert-butyl hydroperoxide as oxidizing agent and vanadyl sulfate as catalyst at room temperature. The versatility of the catalytic protocol is studied with wide variety of substrates.     

Magnetohydrodynamic flow over a vertical stretching surface with suction and blowing

An analysis is presented to investigate the flow and heat transfer characteristics of a vertical stretching surface with suction and blowing, and variable magnetic effects. The magnetic field of variable intensity is applied perpendicular to the surface. The range of the magnetic parameter M investigated is 0.1 to 1.0. The flow is considered steady, incompressible, and three-dimensional. The governing momentum and energy equations are solved numerically. Numerical results are presented for velocity distribution, temperature distribution, surface shear stress, and wall heat transfer rate. Discussion is provided for the effect of the magnetic field strength on the velocity and temperature fields. Received on 26 November 1997     

Sulfonate protecting groups. Synthesis of O- and C-methylated inositols: d- and l-ononitol, d- and l-laminitol, mytilitol and scyllo-inositol methyl ether

Syntheses of d- and l-ononitol, d- and l-laminitol, mytilitol and scyllo-inositol methyl ether starting from myo-inositol are described. One or two of the myo-inositol 1,3,5-orthoformate hydroxyl groups were protected as tosylates. These mono or ditosylates served as key intermediates for the preparation of O- and C-methyl inositols. Racemic 2,4-di-O-tosyl-myo-inositol 1,3,5-orthoformate was resolved as its diastereomeric camphanates. Use of sulfonate groups for the protection of inositol hydroxyl groups resulted in substantial improvement in the overall yield of O- and C-methyl inositols.     

Coordination and profit sharing between a manufacturer and a buyer with target profit under credit option

Several studies have focused on buyer vendor coordination through quantity discount/credit option mechanism but few quantitative models and investigations are available that have explored the mechanism for transfer of surplus generated due to coordination. In this paper, we develop a coordination mechanism through credit option such that both the parties can divide the surplus equitably after satisfying their own profit targets. Two situations are explored here; in the first situation; both the parties have no individual profit target from the business whereas in the second situation, there are individual profit target for both the parties. The proposed mechanism for division of surplus is studied through a numerical study and the impact of different parameter values on the results are examined.     

Reactions of guaianolide

Transformation of the guaianolide cynaropicrin to the pseudoguaianolide skeleton was attempted. Although the desired transformation could not be achieved, the attempt nevertheless led to the synthesis of C-1 and C-4 hydroxylated guaianolides which have been recently isolated from a natural source.     

A geodesic study of the Erez-Rosen space-time

We present the nature of stable trajectories of neutral particles around an object with a quadrupole moment in both the equatorial (=/2) and the polar (=constant) plane.     

Alcoholic solvent‐assisted ligand‐free room temperature Suzuki–Miyaura cross‐coupling reaction

We have observed the enhancing effect of alcoholic solvents in palladium‐catalysed ligand‐free Suzuki–Miyaura reactions. No extra additives or ligands are required for the Suzuki–Miyaura reaction of aryl bromides with arylboronic acids when we carried out the reaction in alcoholic or aqueous alcoholic solvents. Moreover, ethanol or aqueous ethanol is found to be a very good solvent for the Suzuki–Miyaura reaction involving electronically diverse aryl bromides and arylboronic acids under mild and ligand‐free conditions with low catalyst loading. It is observed from Hg(0) poisoning tests that the in situ generated palladium(0) species is the actual catalytic species for the reaction. Copyright © 2015 John Wiley & Sons, Ltd.     

An ambient temperature Sonogashira cross-coupling protocol using 4-aminobenzoic acid as promoter under copper and amine free conditions

A new methodology has been developed based on Pd(OAc)₂ and 4-aminobenzoic acid catalytic system for the Sonogashira cross-coupling reaction at ambient temperature under copper and amine free conditions. The newly developed catalytic system is conveniently applicable to the aryl iodides and terminal acetylenes. The catalytic system is much efficient because of the use of easily available and low cost additive.     

Effect of variable viscosity on boundary layer flow along a continuously moving plate with variable surface temperature

Flow of an incompressible viscous fluid past a continuously moving semi-infinite plate is studied by taking into account variable viscosity and variable temperature. Velocity and temperature profiles are shown graphically whereas the numerical values of the skin-friction and the rate of heat transfer are listed in a table. The effect of different parameters on the flow field is discussed.