Alcohol straight-chain

The question arises, whether and to what extent the dicarboxylic acid 1 is capable of binding other solvents besides ethanol (starting observation, cf. Sect. 1) in the crystal lattice. For this purpose, to begin with, crystallization experiments using further alcohols (straight-chain, branched, univalent and polyvalent) were carried out. It was found that 1 is apt to form crystal inclusions on a large scale, i.e. with alcohols of various constitutions. A list of different examples is given in Table 1 (Entries 1-16). 

Chem. Descrip. Oleyl alcohol straight-chain, monohydric, mono-unsat. 

The fatty acids occur in nature chiefly as glycerides see fats), which constitute the most important part of the fats and oils, and as esters of other alcohols, the waxes. The naturally occurring fatty acids are mostly the normal straight-chain acids with an even number of carbon atoms. 

The deviation of Gibbs monolayers from the ideal two-dimensional gas law may be treated by plotting xA// 7 versus x, as shown in Fig. III-15c. Here, for a series of straight-chain alcohols, one finds deviations from ideality increasing with increasing film pressure at low x values, however, the limiting value of unity for irAfRT is approached. 

If the dependence on temperature as well as on composition is known for a solution, enthalpies and entropies of adsorption may be calculated from the appropriate thermodynamic relationships [82]. Neam and Spaull [147] have, for example, calculated the enthalpies of surface adsorption for a series of straight-chain alcohols. They find an increment in enthalpy of about 1.96 kJ/mol per CH2 group. 

The behavior of insoluble monolayers at the hydrocarbon-water interface has been studied to some extent. In general, a values for straight-chain acids and alcohols are greater at a given film pressure than if spread at the water-air interface. This is perhaps to be expected since the nonpolar phase should tend to reduce the cohesion between the hydrocarbon tails. See Ref. 91 for early reviews. Takenaka [92] has reported polarized resonance Raman spectra for an azo dye monolayer at the CCl4-water interface some conclusions as to orientation were possible. A mean-held theory based on Lennard-Jones potentials has been used to model an amphiphile at an oil-water interface one conclusion was that the depth of the interfacial region can be relatively large [93]. 

Apart from fatty acids, straight-chain molecules containing other hydrophilic end groups have been employed in numerous studies. In order to stabilize LB films chemical entities such as tlie alcohol group and tlie metliyl ester group have been introduced, botli of which are less hydrophilic tlian carboxylic acids and are largely unaffected by tlie pH of tlie subphase. 

Hydrogenation of furfuryl alcohol can yield 2-tetrahydrofurfuryl alcohol, 2-methylfuran, 2-methyltetrahydrofuran, or straight-chain compounds by hydrogenolysis of the ring. Ethoxylation and propoxylation of furfuryl alcohol provide usefiil ether alcohols. 

Urea has the remarkable property of forming crystalline complexes or adducts with straight-chain organic compounds. These crystalline complexes consist of a hoUow channel, formed by the crystallized urea molecules, in which the hydrocarbon is completely occluded. Such compounds are known as clathrates. The type of hydrocarbon occluded, on the basis of its chain length, is determined by the temperature at which the clathrate is formed. This property of urea clathrates is widely used in the petroleum-refining industry for the production of jet aviation fuels (see Aviation and other gas-TURBINE fuels) and for dewaxing of lubricant oils (see also Petroleum, refinery processes). The clathrates are broken down by simply dissolving urea in water or in alcohol. 

Most higher alcohols of commercial importance are primary alcohols secondary alcohols have more limited specialty uses. Detergent range alcohols are apt to be straight chain materials and are made either from natural fats and oils or by petrochemical processes. The plasticizer range alcohols are more likely to be branched chain materials and are made primarily by petrochemical processes. Whereas alcohols made from natural fats and oils are always linear, some petrochemical processes produce linear alcohols and others do not. Industrial manufacturing processes are discussed in Synthetic processes. 

The mixture of carbon monoxide and hydrogen is enriched with hydrogen from the water gas catalytic (Bosch) process, ie, water gas shift reaction, and passed over a cobalt—thoria catalyst to form straight-chain, ie, linear, paraffins, olefins, and alcohols in what is known as the Fisher-Tropsch synthesis. 

Alkyl boric acid esters derived from straight-chain alcohols and aryl boric acid esters are stable to relatively high temperatures. Methyl borate is stable to 470°C (11). Trialkoxyboranes from branched-chain alcohols are much less stable, and boranes from tertiary alcohols can even decompose at 100°C (12). Decomposition of branched-chain esters leads to mixtures of olefins, alcohols, and other derivatives. 

The hydroformylation reaction is carried out in the Hquid phase using a metal carbonyl catalyst such as HCo(CO)4 (36), HCo(CO)2[P( -C4H2)] (37), or HRh(CO)2[P(CgH3)2]2 (38,39). The phosphine-substituted rhodium compound is the catalyst of choice for new commercial plants that can operate at 353—383 K and 0.7—2 MPa (7—20 atm) (39). The differences among the catalysts are found in their intrinsic activity, their selectivity to straight-chain product, their abiHty to isomerize the olefin feedstock and hydrogenate the product aldehyde to alcohol, and the ease with which they are separated from the reaction medium (36). 

Oxidation of Straight-Chain Alcohols. Two methods have been developed. One uses an air oxidation catalyzed by a metal, eg, copper, platinum, etc, whereas the other is a caustic oxidation. Generally, however, fatty alcohols are priced higher on the world market than their corresponding fatty acids and, consequently, these conversions are uneconomical. 

The acid is rather slow to react with aUphatic hydrocarbons unless a double bond or other reactive group is present. This permits straight-chain fatty alcohols such as lauryl alcohol [112-53-8] C22H2 0, to be converted to the corresponding sulfate without the degradation or discoloration experienced with the more vigorous reagent sulfur trioxide. This is important in shampoo base manufacture (see Hairpreparations). 

Alcohols, particularly ethanol [64-17-5] and 2-propanol [67-63-9] are important disinfectants and antiseptics. In the aUphatic series of straight-chain alcohols, the antimicrobial activity increases with increasing molecular weight up to a maximum, depending on the organism tested. For Staphylococcus aureus the maximum activity occurs using amyl alcohol [71-41-0], for Salmonella typhosa, octyl alcohol [111-87-5], CgH gO (43) ioT Mycobacterium tuberculosis... 

The following applications include the removal of straight-chain from branched-chain or cyclic molecules. For example, type 5A sieves will adsorb n-butyl alcohol but not its branched-chain isomers. Similarly, it separates n-tetradecane from benzene, or n-heptane from methylcyclohexane. 

Until comparatively recently the bulk of general purpose phthaiate plasticisers have been based on the branched alcohols because of low cost of such raw material. Suitable linear alcohols at comparative prices have become available from petroleum refineries and good all-round plasticisers are produced with the additional advantage of conferring good low-temperature flexibility and high room temperature resistance to plasticised PVC compounds. A typical material (Pliabrac 810) is prepared from a blend of straight chain octyl and decyl alcohols. 

Problem 27.1 Carnauba wax, used in floor and furniture polishes, contains an ester of a C32 straight-chain alcohol with a C20 straight-chain carboxylic acid. Draw its structure. 

The intensity of the molecular ion in both straight-chain and branched alcohols decreases with increasing molecular weight. Beyond C5, in the case of branched primary alcohols, and C6, in the case of straight-chain primary alcohols, the molecular ion is usually insignificant. 

A primary alcohol is indicated when the m/z 31 peak is intense and will be the base peak for C,-C4 straight-chain primary alcohols. C4 and higher straight-chain primary alcohols lose 18, 33, and 46 Daltons from the molecular ion. Branched aliphatic alco-... 

Primary straight-chain and aromatic alcohols (also look for a large mJz 31 )... 

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