Propane generation

Replacement of either one of the methylene protons of propane generates 2 chloro propane Both methylene protons are equivalent Neither of them is equivalent to any of the methyl protons... 

A bromine radical can abstract either a 1° or a 2° hydrogen from propane, generating either a 1 ° radical or a 2° radical. Calculating AH° using bond dissociation energies reveals that both reactions are endothermic, but it takes less energy to form the more stable 2° radical. 

A total synthesis of karahanaenonfi could be performed expanding a divinylcyclo-propane generated by free radical addition of thiophenol to an alkenylidenecyclopropane, however with low efliciency Preparations of fused heterocycles are possible if a heteroaromatic system is taking part in the sigmatropic process (equation 176). Additional examples demonstrate the accelerating effect of iV-methylation. ... 

The most frequently encountered examples of the first type are the addition of diazoalkanes to 3//-pyrazoles (or addition of two moles of diazoalkane to an acetylene). For example, in the reaction of 2-diazopropane with dimethyl butynedioate, addition of one mole of 2-diazo-propane generated dimethyl 3,3-dimethyl-3/f-pyrazole-4,5-dicarboxylate (1), and addition of a second mole of 2-diazopropane gave dimethyl 4,4,8,8-tetramethyl-2,3,6,7-tetraazabicy-clo[3.3.0]octa-2,6-diene-l,5-dicarboxylate (2) which on photolysis (not thermolysis or sensitized photolysis ) gave a 41% yield of dimethyl 2,2,4,4-tetramethylbicyclo[1.1.0]bu-tane-l,3-dicarboxylate (3). Similar bis-additions are known for dicyano-, diacetyl-, and diben-zoylacetylene, but only the dicyano system gives the bicyclobutane on thermal deazetization. ... 

R R = O) suffers lithium-oxygen co-ordination and monobromocyclo-propane generation (Scheme 65), the configuration being the opposite of that obtained from reduction with tributyltin hydride. In (424), however, there is greater... 

The degree to which allylic radicals are stabilized by delocalization of the unpaired electron causes reactions that generate them to proceed more readily than those that give simple alkyl radicals Compare for example the bond dissociation energies of the pri mary C—H bonds of propane and propene... 

Regardless of the techniques used to purify the KA oil, several waste streams are generated during the overall oxidation—separation processes and must be disposed of. The spent oxidation gas stream must be scmbbed to remove residual cyclohexane, but afterwards will stiU contain CO, CO2, and volatile hydrocarbons (especially propane, butane, and pentane). This gas stream is either burned and the energy recovered, or it is catalyticaHy abated. 

Carbocations generated from alkanes using superacids react with carbon monoxide under mild conditions to form carboxyUc acid (188). In this process isomeric carboxyUc acids are produced as a mixture. However, when the reaction is mn with catalytic amounts of bromine (0.3 mmol eq) in HF-SbF solution, regio-selective carboxylation is obtained. / -Propane was converted almost exclusively to isobutyric acid under these conditions. 

Butane. The VPO of butane (148—152) is, in most respects, quite similar to the VPO of propane. However, at this carbon chain length an important reaction known as back-biting first becomes significant. There is evidence that a P-dicarbonyl intermediate is generated, probably by intramolecular hydrogen abstraction (eq. 32). A postulated subsequent difunctional peroxide may very well be the precursor of the acetone formed. 

Essentially all of the methane [74-82-8] is removed ia the demethanizer overhead gas product. High recovery of ethane and heavier components as demethanizer bottoms products is commonplace. The work that is generated by expanding the gas ia the turboexpander is utilized to compress the residue gas from the demethanizer after it is warmed by heat exchange with the inlet gas. Recompression and deUvery to a natural gas pipeline is performed downstream of the plant. A propane recovery of 99% can be expected when ethane recoveries are ia excess of 65%. 

Many commercial gases are generated by burning hydrocarbons (qv) eg, natural gas or propanes, in air (see Gas, natural Liquified petroleum gas). The combustion process, especially the amount of air used, determines the gas composition. For a given fuel-to-air ratio, the gas composition can be used to determine the water vapor content required to achieve a desired equiUbrium carbon content of the austenite (see Combustiontechnology). 

Fig. 3. Synthesis of fluoxetine (31). 3-ChIoro-I-phenyl-I-propanol reacts with sodium iodide to afford the corresponding iodo derivative, followed by reaction with methylamine, to form 3-(methyl amin o)-1-phenyl-1-propan 0I. To the alkoxide of this product, generated using sodium hydride, 4-fluorobenzotrifluoride is added to yield after work-up the free base of the racemic fluoxetine (31), thence transformed to the hydrochloride (51)...

Acetonitrile oxide was generated from 3,4-dimethylfuroxan oxide by flash vacuum pyrolysis and trapped at -40 °C where its and NMR spectra were examined. Warming to room temperature in the presence of propane produced 3,5-dimethyl-2-isoxazoline (Scheme 108) (79TL2443). The oxide could also be generated by photolysis of furoxan (68CC977). 

Flammability limits for pure components and selected mixtures have been used to generate mixing rules. These apply to mixtures of methane, ethane, propane, butane. 

Fuel - Fuel supplies to boilers, furnaces, gas turbine and engine drivers, etc., are designed with features such as multiple fuels, propane vaporizer backup, and a liquid fuel surge tank, to promote reliabihty. The failure of any one fuel to a process unit or utihty generation facihty is used as the basis for evaluating a potential overpressure. 

The reaction of chlorodifluorotnethane with alkoxide ions generated in low concentration from halide ions and epoxides [28, 29] is an interesting, higher temperature method that gives good to excellent yields of gem-difluorocyclo-propanes from just moderately nucleophilic olefins (equation 9)... 

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