Indian Institute of Technology Ropar

About: Indian Institute of Technology Ropar is a education organization based out in Ropar, India. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 1014 authors who have published 2878 publications receiving 35715 citations.

Measurement-induced operation of two-ion quantum heat machines.

Abstract: We show how one can implement a quantum heat machine by using two interacting trapped ions, in presence of a thermal bath. The electronic states of the ions act like a working substance, while the vibrational mode is modelled as the cold bath. The heat exchange with the cold bath is mimicked by the projective measurement of the electronic states. We show how such measurement in a suitable basis can lead to either a quantum heat engine or a refrigerator, which undergoes a quantum Otto cycle. The local magnetic field is adiabatically changed during the heat cycle. The performance of the heat machine depends upon the interaction strength between the ions, the magnetic fields, and the measurement cost. In our model, the coupling to the hot and the cold baths is never switched off in an alternative fashion during the heat cycle, unlike other existing proposals of quantum heat engines. This makes our proposal experimentally realizable using current tapped-ion technology.

A Quick Access to 1‐(2‐Pyridyl)indoles via Solvent‐Free Ruthenium(II)‐Catalyzed Chemo‐ and Regioselective [2+2+2] Cycloaddition of α,ω‐Diynes and N‐Cyanoindoles

Abstract: A new route to synthesize 1-(2-pyridyl)indole scaffolds via the solvent-free, ruthenium(II)-catalyzed, chemo- and regioselective [2+2+2] cycloaddition reaction of diynes with N-cyanoindoles has been developed with good to excellent yields. Among the various transition metal-based catalysts known for cycloaddition reaction to synthesize pyridine derivatives, chloro(pentamethylcyclopentadienyl)(cyclooctadiene)ruthenium(II) was established to be the best catalyst for this system. This efficient methodology provides 3-substituted 1-(2-pyridyl)indole scaffolds having very close structural similarity with biological drug molecules.

Synthesis of industrially important aromatic and heterocyclic ketones using hierarchical ZSM-5 and Beta zeolites

Abstract: Hierarchical ZSM-5 and Beta zeolites were investigated in the synthesis of wide range of industrially important aromatic/heterocyclic ketones by Friedel–Crafts acylation and benzoylation reactions. For comparative study, conventional ZSM-5 and Beta, and amorphous mesoporous Al-MCM-41 were investigated. Hierarchical zeolites were prepared by multi-ammonium structure directing agents whereas conventional zeolites were prepared by mono-ammonium structure directing agents. Among the catalysts investigated in this study, hierarchical Beta exhibited the highest reactant conversion in the acylation and benzoylation reactions. In this study, the systematic assessment of the catalytic activity of acid catalysts for wide range of aromatic and heterocyclic compounds is shown under one umbrella. To the best of our knowledge, these reactions over hierarchical zeolites (ZSM-5 and Beta) are reported here for the first time. Structure activity relationship is explained based on the physico-chemical properties, molecular size, reactivity of reactants, and reaction mechanism. Catalysts can be easily recovered and reused with negligible loss in the catalytic activity.

Green Synthesis of a Microporous, Partially Fluorinated ZnII Paddlewheel Metal–Organic Framework: H2/CO2 Adsorption Behavior and Solid‐State Conversion to a ZnO–C Nanocomposite

Abstract: A microporous, partially fluorinated metal–organic framework consisting of ZnII dimeric paddlewheel units, formulated as [Zn(hfipbba)(4bpdb)0.5]·H2O (1) [hfipbba = 4,4′-(hexaflouroisopropylene)bis(benzoic acid); 4bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene], was synthesized by room-temperature self-assembly and characterized structurally by single-crystal XRD. Compound 1 adopts a 3D microporous framework structure constituted by six-connected ZnII dimeric paddlewheel nodes with {44.610.8}-net topology. Further, rapid synthesis of phase-pure 1 by green synthetic approaches such as mechanochemical and sonochemical routes was achieved. The 3D framework of 1 houses 1D helical channels with narrow pore dimensions of about 3.11 × 4.17 A and exhibits interesting gas-uptake (H2/CO2) properties. The isosteric heats of adsorption Qst for H2 and CO2 were estimated to be 8.8 and 36.4 kJ mol–1, respectively. Interestingly, solid-state conversion of 1 to phase-pure hexagonal ZnO nanocrystals of 6.1 ± 0.63 nm in size, embedded in carbonaceous layers to form a ZnO–C nanocomposite (NC), occurred on heating of 1 to 600 °C under vacuum for 2 h. The ZnO–C NC was characterized by XRD, UV/Vis, energy-dispersive X-ray, and TEM analyses. The as-synthesized ZnO–C NC exhibits good photocatalytic activity for the degradation of methylene blue.