Hydrocarbon functional

Infrared Spectroscopy (ir). Infrared curves are used to identify the chemical functionality of waxes. Petroleum waxes with only hydrocarbon functionality show slight differences based on crystallinity, while vegetable and insect waxes contain hydrocarbons, carboxyflc acids, alcohols, and esters. The ir curves are typically used in combination with other analytical methods such as dsc or gc/gpc to characterize waxes. 

As each functional group is discussed in future chapters, the spectroscopic properties of that group will be described. For the present, we ll point out some distinguishing features of the hydrocarbon functional groups already studied and briefly preview some other common functional groups. We should also point out, however, that in addition to interpreting absorptions that ore present in an IR spectrum, it s also possible to get structural information by noticing which absorptions are not present. If the spectrum of a compound has no absorptions at 3300 and 2150 cm-1, the compound is not a terminal alkyne if the spectrum has no absorption near 3400 cm -, the compound Is not an alcohol and so on. 

II. Classic Division of the Hydrocarbon Functionalization Cycle into Three Parts... 

Among the very few catalytic systems that allow not only C-H bond activation but also functionalization are those based on platinum(II) catalysts. Soon after the discovery that platinum salts in aqueous solution catalyze H/D exchange in hydrocarbons (9,10 a hydrocarbon functionalization cycle was developed on the basis of this system (11). This cycle is depicted in Scheme 2. 

Radical copolymerization of TFE with hydrocarbon functional monomers has also not been widely used, owing perhaps to the high activity in the reaction with the C—H bond with its high probability of chain transfer to the monomer and the polymer, which is a feature of growing perfluoroalkyl radicals, and to poor chemical stability of the copolymers. 

From this point of view attaching of functional groups to common inexpensive fluoropolymers seemed to be a very attractive way to improve the chemical and thermal stability of the final functional polymer materials in comparison with common hydrocarbon functional polymers, while keeping the costs quite reason-... 

In our study of the simple hydrocarbons, there are only two functional groups. One is a carbon-to-carbon double bond. Hydrocarbons that contain a carbon-to-carbon double bond are alkenes. The other hydrocarbon functional group is a carbon-to-carbon triple bond. Hydrocarbons that contain a triple bond are alkynes. These functional groups are the reactive sites in the alkenes and alkynes. The result is that alkenes and alkynes are more reactive than the alkanes. 

The most common strategy for laboratory scale hydrocarbon functionalization is hydrogen atom abstraction followed by free radical recombination. Although the conversions are often low, the simplicity of the approach can in some cases make this the method of choice for preparing a particular target molecule. A representative procedure is the cyanation of 2,3-dimethylbutane to give a 77% yield of 2,2,3-trimethylbutanenitrile1. 

The above reactions proceed via free radical coupling. An alternative system for photochemically driven hydrocarbon functionalization evidently proceeds via the carbanion, which is obtained from reduction of the initially formed free radical3. The carbanion reacts with acetonitrile to give, after in situ hydrolysis, the methyl ketone, e.g., formation of (tricyclo[3.3.1.13-7]dec-1-yl)ethanone6. 

The preceding examples ofC—H coordination are all intramolecular in nature. Of greater interest, especially with commercial goals in mind, are intermolecular reactions involving hydrocarbons- Functionalizing the alkane constituenls of petroleum under mild conditions is a major challenge in organometallic chemistry and one that... 

D°ub Le Bond isolated from Non-hydrocarbon Functional JSroups... 

The principal saturated hydrocarbon functional groups of concern are methyl, methylene and methyne (—CH3, —CH2—, = CH—). The spectra of typical hydrocarbon mixtures (for example as in gas oil and gasoline) are dominated by two pairs of strong bands in the first overtone and combination regions (5900-5500 cm-1 and 4350-4250 cm-1). These are predominantly methylene (—CH2—). The methyl end groups typically show up as a weaker higher-frequency shoulder to these methylene doublets. 

These photooxygenations represent one of the most important hydrocarbon functionalization reactions available to the synthetic organic chemist. 

Hydrocarbons contain only hydrogen and carbon. The hydrocarbon functional groups include alkanes, alkenes, alkynes, and arenes (aromatic compounds). Simple hydrocarbons have few medicinal applications, but are the feedstock of the petrochemical industry to produce plastics, dyes, solvents, detergents, and adhesives (to name just a few). Therefore, hydrocarbons are essential to the medical field. Additionally, all hydrocarbons are flammable and, therefore, find application as fuels. For example, gasoline is a mixture of hydrocarbons. 

It has become widely recognized over the past several decades that cuticular lipids, especially the hydrocarbons, function in chemical communication in many insect species (Howard, 1993 Nelson and Blomquist, 1995 Blomquist et al., 1998). Semiochemical functions attributed to hydrocarbons include sex attractants... 

Lubricants containing chlorinated hydrocarbons are typically used as antiseizure additives in the metalworking industry. Some chlorine-containing hydrocarbons function by producing iron chloride on the metal surface (Kotvis et al., 1991). The correlation between chemical reactivity and load carrying capacity of oil containing extreme pressure additives can be assumed to be as follows ... 

Alcohols can be regarded as hydroxyl derivatives of hydrocarbons. They can be characterized by the number of hydroxyl groups (monohydric, dihydric, etc.), according to their structure (primary, secondary or tertiary), and by the structure of the hydrocarbon function to which the hydroxyl is attached (aliphatic, cyclic, saturated or unsaturated). 

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