Studies of the acylarylnitrosamine reaction. I. The use of nitrosylsulfuric acid in the preparation of unsymmetrical biaryls

1967 ◽  
Vol 45 (13) ◽  
pp. 1539-1542 ◽  
Author(s):  
Yusuf Ahmad ◽  
M. Ikram Qureshi ◽  
M. Ibrahim Baig
Keyword(s):  
Pure State ◽  
Room Temperature ◽  
Nitrosylsulfuric Acid

Nitrosylsulfuric acid, which is very easy to prepare in a pure state and is quite stable at room temperature, has been found to be a very suitable reagent for the nitrosation of acylarylamines. The nitroso derivatives can be isolated easily, and on decomposition in benzene have yielded unsymmetrical biaryls in improved yields. Some of the nitrosations that could not be achieved earlier have now been accomplished successfully by this method.

Cyclohexyneplatinum(0) Complexes Containing Di-t-butylphenylphosphine, t-butyldiphenylphosphine or Trimethylphosphine

1992 ◽  
Vol 45 (1) ◽  
pp. 135 ◽  
Author(s):  
MA Bennett ◽  
HG Fick ◽  
GF Warnock
Keyword(s):  
Pure State ◽  
Room Temperature ◽  
Main Product ◽  
Similar Reaction ◽  
Molar Proportion ◽  
Sodium Amalgam ◽  
Tertiary Phosphines

Cyclohexyneplatinum (0) complexes Pt(C6H8)L2 [L = PBut2Ph(4), PbutPh2(5)] analogous to the known complex (3) (L=PPh3) have been prepared by reaction of the two-coordinate complexes PtL2 with 1,2-dibromocyclohexene and 1% sodium amalgam. The corresponding tricyclohexylphosphine complex is formed by a similar reaction but it could not be isolated in a pure state. Attempts to prepare analogues of (4) and (5) containing cycloheptyne or cyclooctyne were unsuccessful, possibly because the bulky t-butyl groups of the tertiary phosphines hinder coordination of the larger rings. Bulky tertiary phosphines do not displace PPh3 from (3) but trimethylphosphine reacts with (3) to give successively Pt(C6H8)(PMe3)2(PPh3) (10) and Pt(C6H8)(PMe3)2 (11), as shown by 31P{1H) n.m.r. spectroscopy. The tertiary phosphines in these complexes equilibrate rapidly at room temperature in benzene and only (10) can be isolated as a solid from the reaction. Complexes (4) and (5) react with HCl (1 molar proportion) to give n1-cyclohexen-l-yl complexes trans- PtCl (C6H9)L2 [L= PBut2Ph(6), PButPh2 (7)]. In the absence of air, (4) reacts with methanol at 65°C to give the hydrido complex trans- PtH (C6H9)(PBut2Ph)2 (8). In the presence of oxygen from the air, however, the main product is the dioxygen complex Pt(O2)(Pbut2Ph)2 (9). This represents an unusual example of complete displacement of cyclohexyne from a platinum(0) complex by a π-acceptor ligand.

The radiation chemistry of dihydromyrcene

1967 ◽  
Vol 45 (2) ◽  
pp. 101-108 ◽  
Author(s):  
John L. Brash ◽  
Morton A. Golub
Keyword(s):  
Hydrogen Evolution ◽  
Pure State ◽  
Room Temperature ◽  
Benzene Solution ◽  
Radiation Chemistry ◽  
Cross Linking ◽  
Double Bonds ◽  
Trans Isomerization ◽  
The Cross ◽  
G Value

Dihydromyrcene was irradiated with 1-MeV electrons at room temperature both in the pure state and in benzene solution. The main reactions observed, and their G-values for the pure diisoprene, were loss of unsaturation (~7.8–9.9), cross-linking (or dimerization) (2.4–2.6), evolution of hydrogen (0.81), and trans → cis isomerization (< 0.5). As with squalene, the loss of double bonds in dihydromyrcene occurred only in the cross-linked residue, obtained on distillation of the irradiated isoprenoid. Although the residue (mainly dimer, with some trimer) was considered to be partially cyclized, no cyclization of uncross-linked (monomeric) dihydromyrcene was observed. Dihydromyrcene in 10% benzene solution (by weight) showed trans → cis and cis → trans isomerization with G-values of 0.63 and 1.2, respectively, hydrogen evolution with a G-value of 0.08, and a higher rate of loss of original unsaturation than in the pure state.

scholarly journals Beiträge zur Chemie des Phosphors, 85 Synthese und Eigenschaften der Diphosphirane (t-BuP)2CMe2 und (t-BuP)2CH2 Contributions to the Chemistry of Phosphorus, 85 Synthesis and Properties of the Diphosphiranes (t-BuP)2CMe2 and (t-BuP)2CH2

1978 ◽  
Vol 33 (11) ◽  
pp. 1208-1213 ◽  
Author(s):  
Marianne Baudler ◽  
Franz Saykowski
Keyword(s):  
Ir Spectra ◽  
Elemental Analysis ◽  
Pure State ◽  
Vacuum Distillation ◽  
Room Temperature ◽  
Mass Determination ◽  
Tert Butyl ◽  
Dimeric Compound ◽  
Molecular Mass Determination ◽  
Cyclocondensation Reactions

The first three-membered P2C heterocycles, 1,2-di-tert-butyl-3,3-dimethyl-diphosphirane, (t-BuP)2CMe2 (1), and 1,2-di-tert-butyl-diphosphirane, (t-BuP)2CH2 (2), were synthesized by [2 + 1] cyclocondensation reactions of K(t-Bu)P-P(t-Bu)K with 2,2-dichloropropane and dichloromethane, respectively. Both compounds could be isolated in a pure state by vacuum distillation. Whereas 1 is surprisingly stable under inert condi­tions, 2 dimerizes already at room temperature to form the six-membered cyclocarbaphosphane 1,2,4,5-tetra-tert-butyl-cyclo-3,6-dicarba-1,2,4,5-tetraphosphane, (t-BuP)4(CH2)2 (3).The diphosphiranes 1 and 2 were characterized by elemental analysis, osmometric molecular mass determination, mass, NMR, and IR spectra. The t-butyl groups are situated on opposite sides of the P2C ring, whereas the dimeric compound 3 possesses an “all-trans” configuration of the organyl substituents.

scholarly journals The significance of Vi-phage types F1 and F2 of Salmonella typhi

1951 ◽  
Vol 49 (4) ◽  
pp. 458-470 ◽  
Author(s):  
E. S. Anderson
Keyword(s):  
Typhoid Fever ◽  
Pure State ◽  
Room Temperature ◽  
Salmonella Typhi ◽  
Field Conditions ◽  
Typing Scheme ◽  
Phage Types ◽  
Logarithmic Growth

1. Type F1 will appear in old Dorset egg cultures of Type F2 after storage for months or years at room temperature in the dark.2. It is probable that a similar change is responsible for the appearance of Types F1 and F2 in the same carrier and outbreak of typhoid fever.3. The two types are stable when growing logarithmically in the pure state.4. There is also evidence that the two types are stable under ordinary field conditions.5. Logarithmic growth of F1 in the presence of F2 results in the disappearance of F1.6. This change is caused by a phago carried by F2, which converts F1 into F2.7. The significance of these observations is discussed. It is suggested that the two types retain their status in the typing scheme.

Beiträge zur Chemie des Phosphors, 113 [1, 2] Synthese und Eigenschaften des Azadiphosphirans (t-BuP)2N(i-Pr) / Contributions to the Chemistry of Phosphorus, 113 [1, 2] Synthesis and Properties of the Azadiphosphirane (t-BuP)2N(i-Pr)

1982 ◽  
Vol 37 (5) ◽  
pp. 527-530 ◽  
Author(s):  
Marianne Baudler ◽  
Gabi Kupprat
Keyword(s):  
Nitrogen Atom ◽  
Pure State ◽  
Room Temperature ◽  
Fractional Distillation ◽  
Nmr Spectrum ◽  
Tert Butyl

1-Isopropyl-2,3-di-tert-butyl-1,2,3-azadiphosphirane (1) was synthesized by [2+1] cyclocondensation of Cl(t-Bu)P-P(t-Bu)Cl with (Me3Sn)2N(i-Pr) at 75 °C. 1 could be isolated in pure state by fractional distillation and is stable at room temperature under inert conditions. The temperature independent 31P NMR spectrum indicates that the arrangement at the nitrogen atom is planar, probably due to dative π-bonds from nitrogen to the phosphorus atoms

Bildung von Polychromsaure-tert-butylestern / Formation of tert-Butylpolychromates

1973 ◽  
Vol 28 (9-10) ◽  
pp. 597-599 ◽  
Author(s):  
Werner J. Behr ◽  
Joachim Fuchs
Keyword(s):  
Ir Spectra ◽  
Column Chromatography ◽  
Pure State ◽  
Room Temperature ◽  
Starting Material ◽  
Tert Butanol ◽  
Judicious Choice ◽  
By Products

When the reaction between CrO3 and tert-butanol is carried out about thrice the amount of CrO3 will be used up as is required for the formation of di-tert-butylchromate. That means that polychromates were formed. By a judicious choice of starting material concentrations solutions of almost pure mono, di and trichromates can be produced even though these compounds can be readily interconverted into one another. The monochromate can be separated from by-products via column chromatography and is obtainable as pure solid. The di and trichromate could not be obtained in a pure state because of their ease of decomposition. In solution they are stable at room temperature in the dark for 15-30 min and they can be employed for synthesis. IR spectra indicate that the alkyl portion in these polychromates is bonded similarly as in the monochromate.

scholarly journals IX. A conjugating "yeast."

1901 ◽  
Vol 194 (194-206) ◽  
pp. 467-485 ◽  
Keyword(s):  
Pure State ◽  
Room Temperature ◽  
Yeast Cells ◽  
Hanging Drop ◽  
Central Mass ◽  
Cell Systems ◽  
Naked Eye ◽  
Streak Culture ◽  
Abundant Supply ◽  
White Deposit

The organism described in this paper was obtained from commercial ginger in a flask of saccharose-Mayer solution. On keeping the flask at a temperature of 25° C., fermentation occurred, and a brownish-white deposit was formed. An examination of this deposit showed that it consisted chiefly of yeast-cells. Some of these cells were separated, and fractional series of six plate-cultures each were made. The plates were kept at the ordinary room temperature, and the colonies of yeast-cells were visible to the naked eye in three days. The colonies when a fortnight old appeared to the naked eye as small rounded white masses, about the size of a pin’s head, with regular edges. Under the low power of the microscope the edges appeared fairly regular in those colonies which had developed on the surface of the gelatine, but the submerged colonies had a woolly appearance, due to numerous branches made up chiefly of yeast-cells placed end on end, and comparatively few side branches of such cell-systems, the branches radiating out from a central mass of yeast-cells. By means of hanging-drop cultures in beer-wort gelatine a single cell was selected under the microscope, and its development watched (see Plate 46, fig. 1), until the colony to which it gave rise was large enough to be visible to the naked eye. An infection was then taken from this colony, and further fractional series in beer-wort gelatine made; a streak-culture on beer-wort gelatine being made at the same time from the same infection. From the growths which developed on these streak- and platecultures, an abundant supply of the organism in a pure state was obtained. The streak-culture was the method adopted for keeping a pure stock of the fungus.

Dependence of Intergranular Fracture on Boundary Topography and Cohesion

1973 ◽  
Vol 31 ◽  
pp. 150-151
Author(s):  
J. E. Doherty ◽  
A. F. Giamei ◽  
B. H. Kear ◽  
C. W. Steinke
Keyword(s):  
Grain Boundary ◽  
Room Temperature ◽  
Nickel Base Superalloy ◽  
Boundary Shear ◽  
Room Temperature Ductility ◽  
Solid Solution Matrix ◽  
Nickel Base ◽  
Solution Matrix ◽  
Different Levels ◽  
Base Superalloy

Recently we have been investigating a class of nickel-base superalloys which possess substantial room temperature ductility. This improvement in ductility is directly related to improvements in grain boundary strength due to increased boundary cohesion through control of detrimental impurities and improved boundary shear strength by controlled grain boundary micros true tures.For these investigations an experimental nickel-base superalloy was doped with different levels of sulphur impurity. The micros tructure after a heat treatment of 1360°C for 2 hr, 1200°C for 16 hr consists of coherent precipitates of γ’ Ni3(Al,X) in a nickel solid solution matrix.

Hepatocyte Alterations in Guinea Pigs FED Polychlorinated Biphenyls (PCBs), Dibenzodioxins (PCDD), AND DIBENZOFURANS (PCDF)

1982 ◽  
Vol 40 ◽  
pp. 56-57
Author(s):  
J. N. Turner ◽  
D. N. Collins
Keyword(s):  
Guinea Pigs ◽  
Room Temperature ◽  
Dose Group ◽  
Methyl Cellulose ◽  
Uranyl Acetate ◽  
Target Organ ◽  
Office Building ◽  
Lead Citrate ◽  
Control Groups ◽  
Cooling Fluid

A fire involving an electric service transformer and its cooling fluid, a mixture of PCBs and chlorinated benzenes, contaminated an office building with a fine soot. Chemical analysis showed PCDDs and PCDFs including the highly toxic tetra isomers. Guinea pigs were chosen as an experimental animal to test the soot's toxicity because of their sensitivity to these compounds, and the liver was examined because it is a target organ. The soot was suspended in 0.75% methyl cellulose and administered in a single dose by gavage at levels of 1,10,100, and 500mgm soot/kgm body weight. Each dose group was composed of 6 males and 6 females. Control groups included 12 (6 male, 6 female) animals fed activated carbon in methyl cellulose, 6 males fed methyl cellulose, and 16 males and 10 females untreated. The guinea pigs were sacrificed at 42 days by suffocation in CO2. Liver samples were immediately immersed and minced in 2% gluteraldehyde in cacadylate buffer at pH 7.4 and 4°C. After overnight fixation, samples were postfixed in 1% OsO4 in cacodylate for 1 hr at room temperature, embedded in epon, sectioned and stained with uranyl acetate and lead citrate.

Domain Formation in Synthetic Quartz

1971 ◽  
Vol 29 ◽  
pp. 156-157
Author(s):  
Joseph J. Comer
Keyword(s):  
Electron Beam ◽  
Room Temperature ◽  
Domain Formation ◽  
Synthetic Quartz ◽  
Transmission Electron ◽  
Black Spots ◽  
Diffraction Mode ◽  
Domain Boundaries ◽  
Kikuchi Lines ◽  
Straight Lines

Domains visible by transmission electron microscopy, believed to be Dauphiné inversion twins, were found in some specimens of synthetic quartz heated to 680°C and cooled to room temperature. With the electron beam close to parallel to the [0001] direction the domain boundaries appeared as straight lines normal to <100> and <410> or <510> directions. In the selected area diffraction mode, a shift of the Kikuchi lines was observed when the electron beam was made to traverse the specimen across a boundary. This shift indicates a change in orientation which accounts for the visibility of the domain by diffraction contrast when the specimen is tilted. Upon exposure to a 100 KV electron beam with a flux of 5x 1018 electrons/cm2sec the boundaries are rapidly decorated by radiation damage centers appearing as black spots. Similar crystallographio boundaries were sometimes found in unannealed (0001) quartz damaged by electrons.

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