Chemoselective rhodium-carbenoid reaction with the aromatic nucleus: An efficient methodology for 2-indanones, 2- tetralones and 2-benzosuberones and its application in the synthesis of (±)-ar-Himachalene

1103-111

Preparation of unsymmetrical ketones from tosylhydrazones and aromatic aldehydes via formyl C–H bond insertion

Preparation of ketones by insertion of diazo compounds into the formyl C−H bond of an aldehyde is an attractive procedure, but use of structurally diverse diazo compounds is hampered by preparation and safety issues. A convenient procedure for the synthesis of unsymmetrical ketones from bench-stable tosylhydrazones and aryl aldehydes is reported. The procedure can be performed in one pot from the parent carbonyl compound and needs only a base, with no additional promoters being required

Mitigation Of Voltage Sag Using Dvr

Power quality is one of the major concerns in the era of power system. Power quality problem occurred due to non- standard voltage, current or frequency, that result in a failure of end user equipment. To overcome this problem, Dynamic Voltage Restorer (DVR) is used, which eliminate voltage sag. This paper narrates the application of DVR to optimize the power quality problems such as voltage sag,The DVR is a power electronics based device that is commonly for voltage sagmitigation at the point of connection. A control technique based on a proportional (P) controller is implemented. In fact with the aid of Pulse width modulation (PWM) inverters capable of generating accurate high quality voltage waveforms from the power electronic device. Simulation results shows the effectiveness of proposed method by MATLAB

Microwave specific Wolff rearrangement of α-diazoketones and its relevance to the nonthermal and thermal effect

α-Diazoketones possess high electric dipole moments, as a consequence of the dipolar nature of the diazocarbonyl functional group. The vectorial analysis, theoretical calculations (PM3 and ab initio), and literature reports based on experimental and theoretical calculations reveal a higher dipole moment for the Z-configuration of the diazo functional group. Microwave irradiation of α-diazoketone (1a-m) promotes Wolff rearrangement specifically via the Z-configuration in excellent yields. The dielectric properties of the solvent govern the course of the microwave rearrangement. 3-Diazocamphor (1m) on microwave irradiation in benzylamine exhibits nonthermal effects to furnish exclusively the Wolff rearrangement product (4m), equivalent to its photochemical behavior. In the presence of an aqueous medium, through solvent heating predominates, leading to the formation of a tricyclic ketone (5) as the principal product, arising from an intramolecular C-H insertion. This behavior is similar to its known thermal and transition metal catalyzed reactivity pattern