A Novel Method for the Synthesis of Spiro[indoline‐Pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine]triones by Alum as a Reusable Catalyst

Synthesis of spiro[indoline‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine]trione derivatives by a cyclo‐condensation reaction of indolin‐2‐ones, barbituric acids, and 1,3‐diphenyl‐1H‐pyrazol‐5‐amines with the ionic liquid as an effective green reaction media and in the presence of Alum as a reusable catalyst was reported. Excellent yields of products, green media, use of a reusable catalyst, and short reaction time are the main advantages of this new method.     

Stabilizing chaotic system on periodic orbits using multi-interval and modern optimal control strategies

In this paper, optimal approaches for controlling chaos is studied. The unstable periodic orbits (UPOs) of chaotic system are selected as desired trajectories, which the optimal control strategy should keep the system states on it. Classical gradient-based optimal control methods as well as modern optimization algorithm Particle Swarm Optimization (PSO) are utilized to force the chaotic system to follow the desired UPOs. For better performance, gradient-based is applied in multi-intervals and the results are promising. The Duffing system is selected for examining the proposed approaches. Multi-interval gradient-based approach can put the states on UPOs very fast and keep tracking UPOs with negligible control effort. The maximum control in PSO method is also low. However, due to its inherent random behavior, its control signal is oscillatory.     

An efficient,mild and selective Ullmann‐type N‐arylation of indoles catalysed by Pd immobilized on amidoxime‐functionalized mesoporous SBA‐15 as heterogeneous and recyclable nanocatalyst

A wide range of N‐arylated indoles were selectively synthesized through intermolecular C(aryl)? N bond formation from the corresponding aryl iodides and indoles through Ullmann‐type coupling reactions in the presence of a catalytic amount of Pd immobilized on amidoxime‐functionalized mesoporous SBA‐15 (SBA‐15/AO/Pd(0)) under mild reaction conditions. These cross‐coupled products were obtained in excellent yields under mild conditions at extremely low palladium loading (ca 0.3 mol%), and the heterogeneous catalyst can be readily recovered by simple filtration and reused seven times with loss in its activity. Copyright © 2015 John Wiley & Sons, Ltd.