[Hydroxy(tosyloxy)iodo]benzene: A Tosyloxylating Agent with Selectivity for Ketones in the Reactions with Benzalacetones

The treatment of enolizable ketones containing a conjugated double bond, namely benzalacetones with [hydroxy(tosyloxy)iodo]benzene, leads to regioselective tosyloxylation, thereby giving new compounds (α-tosyloxybenzalacetones).     

Oxidation of α-Benzoyl-O-hydroxyacetophenones Using Iodobenzene Diacetate in Methanolic Potassium Hydroxide: A New Synthesis of 2-Benzoylcoumaran-3-ones

The oxidation of α-benzoyl-o-hydroxyacetophenones (3a-d) using iodobenzene diacetate in methanolic potassium hydroxide provides a new direct method for the synthesis of 2-benzoylcoumaran-3-ones (4a-c) in good yields. The formation of 4a-d is explained by neighb uring group participation.     

Auto-combustion synthesis and properties of Ce0.85Gd0.15O1.925 for intermediate temperature solid oxide fuel cells electrolyte

A typical composition of the system Ce_1 − xGd_xO_2 − δ with x = 0.15 (CGO15) has been synthesized by auto-combustion method. DTA/TGA of the precursor compound indicated the completion of reaction at about 270 °C. Greater than 95% of the theoretical density has been achieved by sintering at 1300 °C for 10 h. Single phase formation in as-burnt stage has been confirmed by its powder X-ray diffraction (XRD) pattern. The structural morphology was studied employing bright field transmission electron micrograph (BFTEM) and high resolution transmission electron micrograph (HRTEM). BFTEM image indicates that particles are highly agglomerated and appear to be dispersed in amorphous matrix. Also BFTEM image reveals that the average particle size is 26 ± 5 nm. The presence of amorphous phase in as-prepared ash was also confirmed by HRTEM and selected area diffraction (SAD). The scanning electron micrograph (SEM) of the thermally etched system shows grains having an average size of 400 nm. Impedance measurements have been made in the frequency range 1 Hz to 1.3 MHz between 200 and 500 °C and the total conductivity was measured. An enhanced conductivity value is observed which may make this system suitable for application as a solid electrolyte material for intermediate temperature solid oxide fuel cells (IT-SOFCs).     

Sequential determination of fat- and water-soluble vitamins in Rhodiola imbricata root from trans-Himalaya with rapid resolution liquid chromatography/tandem mass spectrometry

A rapid method was developed to determine both types of vitamins in Rhodiola imbricata root for the accurate quantification of free vitamin forms. Rapid resolution liquid chromatography/tandem mass spectrometry (RRLC–MS/MS) with electrospray ionization (ESI) source operating in multiple reactions monitoring (MRM) mode was optimized for the sequential analysis of nine water-soluble vitamins (B₁, B₂, two B₃ vitamins, B₅, B₆, B₇, B₉, and B₁₂) and six fat-soluble vitamins (A, E, D₂, D₃, K₁, and K₂). Both types of vitamins were separated by ion-suppression reversed-phase liquid chromatography with gradient elution within 30 min and detected in positive ion mode. Deviations in the intra- and inter-day precision were always below 0.6% and 0.3% for recoveries and retention time. Intra- and inter-day relative standard deviation (RSD) values of retention time for water- and fat-soluble vitamin were ranged between 0.02–0.20% and 0.01–0.15%, respectively. The mean recoveries were ranged between 88.95 and 107.07%. Sensitivity and specificity of this method allowed the limits of detection (LOD) and limits of quantitation (LOQ) of the analytes at ppb levels. The linear range was achieved for fat- and water-soluble vitamins at 100–1000 ppb and 10–100 ppb. Vitamin B-complex and vitamin E were detected as the principle vitamins in the root of this adaptogen which would be of great interest to develop novel foods from the Indian trans-Himalaya.     

A Facile [hydroxy(tosyloxy)iodo]benzene Mediated Synthesis of Symmetrical Triazolo-[3,4-b]-1,3,4-Thiadiazines

Synthesis of the title compounds has been accomplished by a one-pot procedure involving the reaction of 3-substituted-4-amino-5-mercapto-1,2,4-triazoles and a variety of heterocyclic ketones in the presence of [hydroxy(tosyloxy)iodo]benzene.     

A New Route to 2-Aryl-4-quonolones via Thallium(III) p-Tolylsulphonate Mediated Oxidation of 2-Aryl-1,2,3,4-tetrahydro-4-quinolones

Oxidation of 2-aryl-1,2,3,4-tetrahydro-4-quinolones (1a-f) to 2-aryl-4-quinolones (2a-f) using thallium(III) p-tolylsulphonate in refluxing dimethoxyethane has been described. A mechanistic scheme for this new transformation has been proposed.     

Thallium(III) p-Tosylate Mediated Oxidative 2,3-Aryl Rearrangement: A New Useful Route to Ipriflavone and Its Analogs

A new route for the synthesis of ipriflavone, an antiosteoporotic agent, is described that has four steps and 60% yields starting from resacetophenone (2). The key step of the present methodology is thallium(III) p-tosylate mediated oxidative 2,3-aryl rearrangement of flavanone to generate the isoflavone ring system of ipriflavone in a highly efficient manner.     

Dispersion relation and relative intensity for double-plasmon satellites

An expression for the dispersion relation and the relative intensity of double-plasmon oscillations and satellites has been derived by extending the dispersion relation and the extended Bohm and Pines Hamiltonian to second order. The calculated value of the relative intensity of the double-plasmon satellite for Be agrees fairly well with the value observed experimentally by other workers.     

Sound velocity in water vapour

The effective potential is used to calculate the sound velocity of water vapour. The agreement between theoretical and experimental values confirms the validity of the effective potential.