Novel polycyclic heterocycles. XIV. 1,2-Dihydro-4-(trifluoromethyl)-3H-8H-quino[1,8-ab][4,1]benzoxazepin-3-one and its derivatives

Procedures for the isolation of 1,2-dihydro-4-(trifluoromethyl)-3H,8H-quino[1,8-ab][4,1]-benzoxazepine, 3 , from reaction mixtures containing 3 as the minor component, and the isomer, 1,2-dihydro-11-(trifluoromethyl)-3H,7H-quino[8,1-cd][1,5]benzoxazepin-3-one, 2 , as the major component, are described. The reactivity of 3 toward hydroxylamine and aromatic aldehydes has been investigated and the preparation of derivatives with those reactants is described.     

Extraction and flame spectrophotometric determination of palladium and rhodium

Solvent extraction methods involving toluene, chloroform, 4-methyl-2-pentanone and pentyl acetate were studied for palladium and rhodium chelates. The palladiurn-salicylaldoxime chelate was extracted quantitatively into 4-methyl-2-pentanone at pH 3. The rhodium-diethyldithiocarbamate chelate was completely extracted into 4-methyl-2-pentanone at pH 8. The optimum combustion conditions for each of the organic extracts were then studied. The position of maximum emission intensity in the flame mantle was determined for each chelate and solvent system ; readings were taken at 363.5 mμ for palladium, and 369.2 mμ for rhodium. For palla-dium, when 4-methyl-2-pentanone was used instead of water as solvent, the emission intensity increased 21-fold. For rhodium, this kctone increased the sensitivity 27 times compared with water. A method is suggested for the separation and determination of palladium and rhodium in the same sample.     

The kinetics of oxidation of low molecular weight aldehydes by potassium ferrate

Summary Oxidation of simple aldehydes is shown to follow a mixed order rate equation(¹), which contains three terms: the first, first order in the concentration of potassium ferrate (K₂FeO₄); the second, second order in K₂FeO₄; and the third contains the conditional rate constants which are substrate (aldehyde) concentration dependent. The third term is first order dependent on (K₂FeO₄). Aldehydes studied included chloral, acetaldehyde, and trimethylacetaldehyde.     

The kinetics of oxidation of simple aliphatic sulphur compounds by potassium ferrate

Potassium ferrate (K₂FeO₄) is highly soluble in water and a very strong oxidizing agent^{(1, 2)}. Other properties include a strong bacteriacidal action which has been documented by Murmann and Robinson⁽¹⁾. These characteristics, and others, suggest that potassium ferrate would be useful in the advanced treatment of municipal waste water. The efficiency of oxidation of various organic compounds by potassium ferrate must be investigated before conclusions can be drawn.When K₂FeO₄ is placed into aqueous solution a purple colour is produced which disappears as K₂FeO₄ is reduced. At a spectrophotometric wavelength of 505 nm this affords a convenient method for measuring the decomposition kinetics of K₂FeO₄.Rate constants were obtained by algorithmic analysis of spectral absorbance data by the Cornell method⁽³⁾. This work will present a mechanism of reaction for oxidation of simple aliphatic sulphur compounds by potassium ferrate. The oxidation of simple aliphatic sulphur compounds produces the corresponding sulphoxide or sulphone^{(4, 5)} Compounds studied included dimethyl sulphoxide, diethylsulphide, dimethylsulphone, and 2,2-thiodiethanol.     

Judge Nonverbal Communication on Trial: Do Mock Trial Jurors Notice?

This study investigated jurors' reactions to judges' nonverbal communication in mock trials. Participants in 80 mock juries viewed taped segments of direct and cross examination that varied the judges' level of nonverbal involvement. Comments about the judge were solicited in predeliberation questionnaires and unsolicited comments obtained from dialogue that occurred during mock jury deliberations. The investigation found that jurors are aware of nonverbal cues from judges, particularly negative behaviors. Although the high- and low-involved judges solicited roughly the same number of comments, more negative comments were made about the judge displaying low than high nonverbal involvement. The results also revealed that jurors made more negative comments than positive ones. Overall, jurors are most aware of a judge's lack of involvement and apparent bias. Discussion focuses on ways to minimize the influence of judge nonverbal communication on jurors.     

Membrane proteins: adapting to life at the interface

A recent publication by Cravatt and colleagues which describes the structure of an integral membrane protein (FAAH) highlights that the structural differences between membrane proteins and soluble proteins are not as disparate as is sometimes believed.     

Fragmentation studies on monensin A and B by accurate-mass electrospray tandem mass spectrometry

Monensin A and B were studied by electrospray ionisation tandem mass spectrometry (ESI-MS/MS) and the fragment ions were confirmed by accurate-mass measurements. Analyses were performed on both a quadrupole time-of-flight (QTOF) and a Fourier-transform ion cyclotron resonance (FTICR) mass spectrometer. The analysis revealed that fragment ions were produced by Grob-Wharton fragmentations and pericyclic rearrangements in addition to various simple neutral losses. A study of the protonated and sodiated sodium salt revealed different fragmentation pathways for these species, thus complementary structural information could be gained. A complete fragmentation pathway of monensin A and B protonated sodium salt [(M-H+Na)+H])+) and sodiated sodium salt [(M-H+Na)+Na](+) is proposed. MS(3) analysis confirmed the separate fragmentation pathways.     

Thermal analysis of cobalt,nickel and copper complexes of 2-aminothiazole

The thermal decomposition of 2-aminothiazole (2-amt) complexes of general formula M(2-amt)₂X₂ [M = Co(II) and Cu(II)] and Ni(2-amt)₄X₂ [X = Cl and Br] have been studied in air and argon by TG and DTG as well as by DTA in nitrogen; end products from the decompositions in air have been characterised by X-ray powder diffraction. Decomposition stoichiometries have been proposed and factors governing the thermal decomposition have been discussed.     

High-throughput approaches for the discovery and optimization of new olefin polymerization catalysts

The discovery of new olefin polymerization catalysts is currently a time-intensive trial-and-error process with no guarantee of success. A fully integrated high-throughput screening workflow for the discovery of new catalysts for polyolefin production has been implemented at Symyx Technologies. The workflow includes the design of the metal-ligand libraries using custom-made computer software, automated delivery of metal precursors and ligands into the reactors using a liquid-handling robot, and a rapid primary screen that serves to assess the potential of each metalligand-activator combination as an olefin polymerization catalyst. "Hits" from the primary screen are subjected to secondary screens using a 48-cell parallel polymerization reactor. Individual polymerization reactions are monitored in real time under conditions that provide meaningful information about the performance capabilities of each catalyst. Rapid polymer characterization techniques support the primary and secondary screens. We have discovered many new and interesting catalyst classes using this technology.     

Green chemical functionalization of single-walled carbon nanotubes in ionic liquids

Single walled carbon nanotubes (SWNTs) are exfoliated and functionalized predominantly as individuals by grinding them for minutes at room temperature with aryldiazonium salts in the presence of ionic liquids (ILs) and K(2)CO(3). This constitutes an extremely rapid and mild green chemical functionalization process for obtaining the individualized nanotube structures. A number of ILs and various reaction conditions were surveyed. Raman, XPS, UV/vis/NIR spectroscopies, thermogravimetric analysis, and atomic force and transmission electron microscopies were used to characterize the products.