P-Dioxane

ANTIBIOTICS - BETA-LACTAMS - BETA-LACTAMASE INHIBITORS] (Vol 3) 3,6-Dimethyl-p-dioxane-2,5-dione [95-96-5]... 

Chemical Designations - Synonyms Di (Ethylene Oxide) Dioxan p-Dioxane Chemical Formula CH2CH2OCH2CH2O... 

Similar dehydrofluorination occurs with polyfluorinated heterocycles. 2,2-Bis(trifluoromethyl)-3,4-difluorooxetane gives 3-fluoro-4,4-bis(trifluoromethyl)-2-oxete [19] (equation 17), and heptafluoro-p-dioxane yields hexafluoro-p dioxene [20] (equation 18)... 

Morrison and Migdalof (Ref 14) irradiated o-nitrotoluene and p-nitrotoluene with a Pyrex-filtered mercury lamp using D20 and p-dioxane as solvents. C-D bonds formed with o-nitrotoluene, with no C-D formation for p-nitro-toluene - ... 

Obtemperanskaya and Kareva25 determined a, /J-unsaturated ketones and sulphones by adding sodium sulphite to the sample in p-dioxan. After 5-10 min they titrated with standard sulphuric acid potentiometrically or to thymolphthalein ... 

A stainless steel column (4.6 mm internal diameter by 250 mm length) packed with 4 micron Zorbax Octadecylsilane (ODS) (Dupont) was equilibrated with 78 % acetonitrile in water at a flow rate of 2.0 ml/min provided by a Spectraphysics, model 8700, pump and controller. The effluent was monitored at 215 nm using a Jasco Uvidec 100 V ultraviolet detector. Peaks were recorded and calculations performed by a Spectraphysics recording integrator, model 4270. Samples, containing 5 mg/ml of material dissolved in p-dioxane, were applied to the column automatically with a Micromeritics autosampler, model 725, equipped with a 10 microliter loop. Some analyses were performed on a Hewlett-Packard HPLC, model 1090, equipped with a diode array detector. 

Spectral-grade p-dioxane from MC and B Manufacturing Chemists or Mallinckrodt Chemical Works was dried over Linde type 4A molecular sieves. The checkers degassed the solvent prior to use as described in Note 3. 

Dioxane p-Dioxane (8) 1,4-Dioxane (9) (123-91-1) 3-Aminopropanoic acid hydrochloride /3-Alanine, hydrochloride (8, 9) (6057-90-5)... 

Like the carbodiimide method, the mixed anhydride method results in an amide complex (Table 5, Figure 17). The acid-containing hapten is dissolved in a dry, inert, dipolar, aprotic solvent such as p-dioxane, and isobutyl chloroformate is added with an amine catalyst. The activated mixed anhydride is chemically stable and can be isolated and characterized. The aqueous protein solution is added to the activated acid and the pH is maintained at around 8.5. A low temperature (around 10 °C) is necessary during the reaction to minimize side reactions. 

Raney nickel catalyst evaporated with small amounts of methanol, ethanol, isopropanol, pentanol, acetone, benzene, cyclohexane or p-dioxane and then heated towards 200°C eventually explodes See 1,4-Dioxane Nickel... 

In table I we present the molar Kerr constants and mean square dipole moments of three fluorinated polymers, poly (trifluoroethylene) (PFjE), polylvinylidene fluoride) (PVF2) and poly(fluoromethylene) (PFM), dissolved in p-dioxane. The results show the sensitivity of mK to the degree and type of fluorination varying over an order of magnitude and also changing sign. Calculations of mK and for comparison are in progress (5). 

It should be noted at this point that primary and secondary reaction products can be distinguished not only by kinetic data (13) but also by suppression of the secondary reactions. E.g substitution of 2,2,2-trifluoroethanol for p-dioxane as solvent for HCoCCO) suppresses homologation and methane formation addition of a phosphine to give the less acidic catalyst HCo(CO)3PR3 has the same effect, as has the substitution of the less acidic catalyst HMn(CO)5. 

F. Kinetic Isotope Effect. One of the more important observations regarding the cobalt-based homogeneous CO hydrogenation system is that the substitution of gaseous deuterium for gaseous hydrogen causes an inverse (i.e. kflkinetic isotope effect, kj T2)/kH(2)= 0.73 at 180° in p-dioxane (13b). Because... 

Synonyms AI3-01055 BRN 0102551 CCRIS 269 Diethylene dioxide 1,4-Diethylene dioxide Diethylene ether Diethylene oxide Diokan 1,4-Dioxacyclohexane p Dioxacyclohexane Dioxan Dioxane-1,4 p-Dioxane para-Dioxane Dioxyethylene ether DIO DOX 1,4-DOX EINECS 204-661-8 Ethylene glycol ethylene ether Glycol ethylene ether NCI-C03689 NE 220 NSC 8728 RCRA waste number U108 Tetrahydro-1,4-dioxin Tetrahydro-p-dioxin UN 1165. 

Dioxane, see 1,4-Dioxane Dioxane-1,4, see 1,4-Dioxane p-Dioxane, see 1,4-Dioxane... 

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