Hydrocarbons from aldehydes

Hydrocarbons from aldehydes Degradation with loss of 1 C-atom... 

Copper chromite-carbon Hydrocarbons from aldehydes... 

It is convenient to consider the indiflferent or neutral oxygen derivatives of the hydrocarbons—(a) aldehydes and kelones, (b) esters and anhydrides, (c) alcohols and ethers—together. All of these, with the exception of the water-soluble members of low molecular weight, are soluble only in concentrated sulphuric acid, i.e., fall into Solubility Group V. The above classes of compounds must be tested for in the order in which they are listed, otherwise erroneous conclusions may be drawn from the reactions for functional groups about to be described. 

Our experience to this point has been that C—H bonds are not very acidic Com pared with most hydrocarbons however aldehydes and ketones have relatively acidic protons on their a carbon atoms pA s for enolate formation from simple aldehydes and ketones are m the 16 to 20 range... 

AROMATIC HYDROCARBONS FROM AROMATIC KETONES AND ALDEHYDES 1,1 -DIPHENYLETH ANE (I,l -Ethylidenebisbenzene)... 

Abomatic Hydrocarbons from Aromatic Ketones and Aldehydes... 

ALCOHOL represents a convenient method of converting allyl alcohol to 2-substituted 1-propanols, while a one-pot reaction sequence of alkylation (alkyl lithium) and reduction (lithium—liquid ammonia) provides excellent yields of AROMATIC HYDROCARBONS FROM AROMATIC KETONES AND ALDEHYDES. 

Alcohols, primary, 56,40 ALDEHYDES, acetylenic, 55, 52 aromatic, aromatic hydrocarbons from, 55,7... 

The decarboxylation of carboxylic acid in the presence of a nucleophile is a classical reaction known as the Hunsdiecker reaction. Such reactions can be carried out sometimes in aqueous conditions. Man-ganese(II) acetate catalyzed the reaction of a, 3-unsaturated aromatic carboxylic acids with NBS (1 and 2 equiv) in MeCN/water to afford haloalkenes and a-(dibromomethyl)benzenemethanols, respectively (Eq. 9.15).32 Decarboxylation of free carboxylic acids catalyzed by Pd/C under hydrothermal water (250° C/4 MPa) gave the corresponding hydrocarbons (Eq. 9.16).33 Under the hydrothermal conditions of deuterium oxide, decarbonylative deuteration was observed to give fully deuterated hydrocarbons from carboxylic acids or aldehydes. 

As alkylaromatic hydrocarbon (toluene, p-xylene, etc.) is oxidized, aldehydes appear radicals and peracids formed from them play an important role. First, aldehydes react rapidly with the Co3+ and Mn3+ ions, which intensifies oxidation. Second, acylperoxyl radicals formed from aldehydes are very reactive and rapidly react with the initial hydrocarbon. Third, aldehydes form an adduct with primary hydroperoxide, which decomposes to form aldehyde and acid. 

Organometallic compounds or carbanions undergo a number of reactions in which the carbanion or carbanion-like moiety of the organometallic compound acts as a nucleophilic displacing agent. Examples are the formation of hydrocarbons from alkyl halides, alkyl halides from halogens, and ketones from acid chlorides or esters. The latter two reactions are closely related to the base-catalyzed condensations and are perhaps additions as well as displacement reactions. Related addition reactions are the carbonation of organometallic compounds and the addition to ketones or aldehydes. 

On the basis of their findings they contend that the effect of almost any compound -hydrocarbons, alcohols, aldehydes, acids, amines, nitro-compounds, H20, H2S, S02, NH3 - can be co-catalytic or inhibitory, according to its concentration [66]. They extend quite unnecessarily the concept of co-catalyst to cover any substance which enhances the DP, and they thereby confuse and debase the originally perfectly precise meaning of the term co-catalyst a substance the presence of which is essential for the functioning of the catalyst [22, 71]. It follows of course from this definition that evidence on co-catalytic activity can be obtained only from rate measurements, and never from studies of DP. 

Possible slight effects from carboxylic acids, anhydrides, aromatic and aliphatic hydrocarbons, alcohols, aldehydes, ketones, esters, chlorinated solvents... 

AltshuUer. A. P.. D. L. Klosterman, P. W. Leach. I. J. Hindawi, and J. E. Sigsby. Jr. Products and biological effects from irradiation of nitrogen oxides with hydrocarbons or aldehydes under dynamic conditions. Int. J. Air Water Pollut. 10 81-96, 1966. 

That is, it abstracts from saturated hydrocarbons and aldehydes and adds to unsaturated hydrocarbons. As discussed in Chapter 6, the reactions with aromatic hydrocarbons are generally too slow to be important in the troposphere the exceptions are particular compounds such as the cresols where the reaction is rapid. 

Different fractions from the extracts of pork fat were analyzed for volatile compounds by the GLC/MS method of Suzuki and Bailey (25). Fifty-six compounds consisting of 13 hydrocarbons, 15 aldehydes, 4 ketones, 3 alcohols, 6 phenols, 9 carbotylic adds, 1 ester and 5 heterocyclics were identified and quantified in extracts from pork fat heated at 160°C for 1 hr. 

WATER-AIR EQUILIBRATION. McAuliffe (6) introduced a multiple phase equilibrium procedure for the qualitative separation of hydrocarbons from water-soluble organic compounds. For n-alkanes, more than 99% were found to partition in the gas phase after two equilibrations with equal volumes of gas and aqueous solution. Cycloalkanes require three equilibrations to be essentially completely removed, and oxygen-containing organic compounds (e.g., alcohols, aldehydes, ketones, and acids) remain in the aqueous layer. Thus, after equilibration with equal volumes of gas, an immediate clue is given regarding the identification of the compound. More details of this technique can be found in Chapter 7. 

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