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Hydrocarbon, aliphatic yield

If arylsulphonylnitrenes are generated in aliphatic hydrocarbons, better yields of hydrogen abstraction products as in the case of alkylnitrenes are obtained. Thermolysis of p-toluenesulphonylazide in cyclohexane 25> gave 5% yield of p-toluenesulphonylamide, whereas 40% yield was reported also 58>. Thermal decomposition of o-substituted phenylazides 20, 21, 22 in dodecane via abstraction afforded amides 23, 24, 25. [Pg.103]

DFG MAK Confirmed Animal Carcinogen, Suspected Human Carcinogen SAFETY PROFILE Confirmed carcinogen. Poison by ingestion. Moderately toxic by inhalation and skin contact. Experimental reproductive effects. A skin and severe eye irritant. Mutation data reported. Moderately flammable by heat, flames (sparks), or powerful oxidizers. See also v LLYL COMPOUNDS and CHLORINATED HYDROCARBONS, ALIPHATIC. When heated to decomposition it yields highly toxic Cr. To fight fire, use water (as a blanket), spray, mist, dry chemical. [Pg.1373]

Di-iododimethylsilane appears to be an effective reagent for the mild deoxygenation of a-arylalkanols to the corresponding hydrocarbon. Aliphatic alcohol methanesulphonates are selectively reduced in good yield by an electrochemical method. The reaction is performed in a divided cell with a lead cathode and a platinum anode in dry DMF containing tetraethylammonium toluene-p-sulphonate. Yields are in the range 57—87%, and groups such as esters, olefins, nitriles, and even epoxides are inert under these conditions. ... [Pg.1]

Acetophenone.—The Fnedel-Crafts reaction, of which this pieparation is a type, consists in the use of anhydious aluminium chlonde for effecting combination between an aromatic hydrocarbon or its deiivative on the one hand, and a halogen i,Cl 01 Bi) compound on the othei. The leaction 13 always accompanied by the evolution of hydiochloiic or hydio-bromic acid, and the product is a compound with AlCl-j, which decomposes and yields the new substance on the addition of watei. This reaction has been utilised, as in the present case, (r) for the prepaiation of ketones, in which an acid chloiide (aliphatic or aromatic) is employed,... [Pg.309]

NMe is now commercially available and is prepd by the vapor phase nitration of methane at a ratio of 9 moles of methane to I mole of nitric acid at 475° and a residence time of 0.18sec (Ref 12) or by the similar nitration of aliphatic hydrocarbons (Ref 8). Other prepns are from Me sulfate and Na nitrite (Ref 26) by the oxidn of Me amine with dinitrogen trioxide in the gas phase or in methylene chloride, yield 27%... [Pg.87]

Aliphatic hydrocarbons such as hexane also have been reported to react with PCI3 and AICI3. Surface-active esters of phosphinic acids are obtained in good yields by treatment of the intermediate addition compound with an alcohol or phenol followed by hydrolysis [172] see Eqs. (103) to (105) ... [Pg.587]

A further difficulty arises during preparative electrolyses in aprotic solvents because of the bulk pH change which commonly occurs. Thus cathodic reductions often require proton abstraction from the solvent in order to yield stable products, while many anodic oxidations, mcluding those of aromatic and aliphatic hydrocarbons, give rise to a quantitative yield of proton and the consequent changes in the pH. of the electrolysis media would be expected to lead to a variation in the products with the duration of the electrolysis. Unfortunately, the pH can be a very difficult parameter to control in aprotic solvents and most work reported in the literature has been carried out in unbuffered conditions. In the case of oxidations, organic bases, e.g. pyridine, have... [Pg.181]

The oxidation by Cr(VI) of aliphatic hydrocarbons containing a tertiary carbon atom has been studied by several groups of workers. Sager and Bradley showed that oxidation of triethylmethane yields triethylcarbinol as the primary product with a primary kinetic isotope effect of about 1.6 (later corrected by Wiberg and Foster to 3.1) for deuterium substitution at the tertiary C-H bond. Oxidations... [Pg.293]

The process is conducted at 700 °C. It yields semicoke, which is popular as a smokeless domestic fuel. It can at times be used in boiler also to avoid smoke. Yield of coke oven gas is less, of tar high, and of ammonia less. Calorific value of coke oven gas generated is more. The process produces aliphatic natured tar. Following carbonization the coke discharging process is difficult as it swells extensively but does not shrink much upon carbonization. Free carbon in tar (produced from the cracking of hydrocarbons) is less Coke produced is weaker. Volatile matter in the coke produced is more. Hydrogen content in the coke oven gas is less. [Pg.95]

Arylsulphonyl nitrenes usually give better yields of hydrogen-abstraction products from aliphatic hydrocarbons. -Toluenesulphonyl azide gave a 5% yield of -toluenesulphonamide on thermolysis in cyclohexane... [Pg.21]

Second, some organisms are able to incorporate longer pendent chains yielding another class of PHA medium chain length PHA, poly(HAMCL). Poly (HAmcl) is specifically accumulated by fluorescent pseudomonads. When aliphatic hydrocarbons like n-alkane, n-alkanoate, or n-alkanol serve as feedstocks for Pseudomonas oleovorans the resulting PHA is a random copolymer... [Pg.262]

Numerous autoxidation reactions of aliphatic and araliphatic hydrocarbons, ketones, and esters have been found to be accompanied by chemiluminescence (for reviews see D, p. 19 14>) generally of low intensity and quantum yield. This weak chemiluminescence can be measured by means of modern equipment, especially when fluorescers are used to transform the electronic excitation energy of the triplet carbonyl compounds formed as primary reaction products. It is therefore possible to use it for analytical purposes 35>, e.g. to measure the efficiency of inhibitors as well as initiators in autoxidation of polymer hydrocarbons 14), and in mechanistic studies of radical chain reactions. [Pg.72]

Together with singly charged ions doubly and multiply charged ions may also arise in the ionization process. However, the number of doubly charged and especially of multiply charged species is much lower. The yield of these ions depends on the structure of a molecule and on the experimental conditions. For example, polycyclic aromatic hydrocarbons give more ions of these types compared to aliphatic or monoaromatic compounds. [Pg.129]

The next step in complexity are systems in which alkylation competes with hydride transfer to give dimeric alkyl cations which, when hydride abstraction occurs, yield dimeric saturated hydrocarbons (equation 14). This reaction path for cyclic aliphatic alcohols and olefins is often accompanied by some rearrangement (Deno etal., 1964 Pittman, 1964). [Pg.330]

Classical organic chemistry provides a wide variety of potential analytes for electron ionization, the only limitation being that the analyte should be accessible to evaporation or sublimation without significant thermal decomposition. These requirements are usually met by saturated and unsaturated aliphatic and aromatic hydrocarbons and their derivatives such as halides, ethers, acids, esters, amines, amides etc. Heterocycles generally yield useful El spectra, and flavones, steroids, terpenes and comparable compounds can successfully be analyzed by El, too. Therefore, El represents the standard method for such kind of samples. [Pg.217]

Table 22.1), which has been modified by appropriate substitutions to yield the desired molecule. Thus, aliphatic hydrocarbons can be built up from methane by repeated substitutions of methyl groups for hydrogen atoms. Other compounds are formed by substitution of functional groups for CHn groups. The heat capacity constants are those for a cubic polynomial in the temperature, which are similar to those discussed in Chapter 4. [Pg.512]

Somewhat less frequent than the reductions of aliphatic ketones to secondary alcohols and to hydrocarbons are one-electron reductions to pinacols. These are accomplished by metals such as sodium, but better still by magnesium or aluminum. Acetone gave 43-50% yield of pinacol on refluxing with magnesium amalgam in benzene [140], and 45% and 51% yields on refluxing in methylene chloride or tetrahydrofuran, respectively [825. ... [Pg.109]


See other pages where Hydrocarbon, aliphatic yield is mentioned: [Pg.105]    [Pg.45]    [Pg.920]    [Pg.460]    [Pg.28]    [Pg.341]    [Pg.599]    [Pg.298]    [Pg.182]    [Pg.693]    [Pg.60]    [Pg.129]    [Pg.378]    [Pg.227]    [Pg.358]    [Pg.364]    [Pg.21]    [Pg.7]    [Pg.79]    [Pg.348]    [Pg.230]    [Pg.339]    [Pg.390]    [Pg.204]    [Pg.19]    [Pg.54]    [Pg.261]    [Pg.243]    [Pg.207]    [Pg.431]    [Pg.390]    [Pg.53]    [Pg.340]   
See also in sourсe #XX -- [ Pg.123 ]




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Aliphatic hydrocarbons

Hydrocarbon yields

Hydrocarbonization yield

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