Monofunctional alcohols

Polyether Polyols. Polyether polyols are addition products derived from cyclic ethers (Table 4). The alkylene oxide polymerisation is usually initiated by alkah hydroxides, especially potassium hydroxide. In the base-catalysed polymerisation of propylene oxide, some rearrangement occurs to give aHyl alcohol. Further reaction of aHyl alcohol with propylene oxide produces a monofunctional alcohol. Therefore, polyether polyols derived from propylene oxide are not truly diftmctional. By using sine hexacyano cobaltate as catalyst, a more diftmctional polyol is obtained (20). Olin has introduced the diftmctional polyether polyols under the trade name POLY-L. Trichlorobutylene oxide-derived polyether polyols are useful as reactive fire retardants. Poly(tetramethylene glycol) (PTMG) is produced in the acid-catalysed homopolymerisation of tetrahydrofuran. Copolymers derived from tetrahydrofuran and ethylene oxide are also produced. 

H. Muller, G. Stoll, C. P. Herold, and S. von Tapavicza. Application of selected ethers of monofunctional alcohols in drilling fluids (Verwendung ausgewahlter Ether monofunktioneller Alkohole in Bohrspiilungen). Patent EP 391251, 1990. 

One may use the stronger term chirality discrimination when a substantial suppression of one intermolecular diastereomer with respect to the other occurs. This requires multiple strong interactions between the two molecular units and therefore more than simple monofunctional alcohols. Some examples where one of the molecules involved is a chiral alkanol are reported in Refs. 112 and 119 121. Pronounced cases of higher-order chirality discrimination have been observed in clusters of hydroxy esters such as methyl lactate tetramers [122] and in protonated serine octamers [15,123,124]. The presence of an alcohol functionality appears to be favorable for accentuated chirality discrimination phenomena even in these complex systems [113,123,125,126]. Because the border between chirality recognition and discrimination is quite undefined, it is suggested that the two may be used synonymously whenever both molecular partners are permanently chiral [127]. 

Molecular Connectivity- Kow Relationships Kier and Hall [34] have analyzed the correlation between K0w and various MCIs for hydrocarbons and monofunctional alcohols, ethers, ketones, acids, esters, and amines. Analogous relationships have been studied by Finizio et al. [35] for substituted s-triazines and by Govers et al. [36] for thioureas. 

In all reported examples on the diols, the primary alcohols were found to react faster than the secondary ones, as expected and previously shown for telomerization of monofunctional alcohols [40]. The improved selectivity for the mono-telomer over the di-telomer observed for most of the non-linear diols over the linear ones can be attributed to this difference in reactivity. 

It now remains for us to consider the oxidation of monofunctional alcohols and molecules containing the -OH group remote from other functions. The conversion of methanol to formaldehyde (methanal) can be performed either by dehydrogenation (difficult, see Chapter 9) or by oxidative dehydrogenation according to the equation ... 

Acetalization equilibria of carbonyl compounds are shifted toward the side of the acetal when the reaction is carried out with one equivalent of a diol rather than with two equivalents of an alcohol (Figure 7.18). The reason for this is that now the reaction entropy is no longer negative Using the diol, two product molecules are produced from two molecules of starting material, whereas during an acetalization with monofunctional alcohols, two product molecules are produced from three molecules of start-... 

When this reaction is conducted on ketones, instead of aldehydes, the equivalent species to the hemiacetal and acetal are now called hemiketal and ketal respectively. However, when simple ketones are reacted with normal monofunctional alcohols, the reaction rarely goes to completion, unlike the situation with aldehydes where the reaction proceeds smoothly. Yet, when a 1,2-diol is reacted with a ketone, then the reaction goes to completion much more readily. Write the complete reaction sequence for the formation of the cyclic ketal starting from propanone and 1,2-ethandiol, under acidic conditions. Also, suggest why the product between one molecule of each reagent is favoured over the alternative product that would result from the reaction between two molecules of the diol and one of the ketone. 

The bulk of aliphatic ester plasticizers are derived from adipic, sebacic and azelaic acid esterified with linear or branched monofunctional alcohols of short to medium-chain length, for example, dioctyl adipate (DOA, di[2-ethylhexyl]adipate), diiso-nonyl adipate (DINA), di[n-butyl]sebacate (DBS). Adipate, azelate and sebacate plasticizers are distinguished by their low viscosity, thus making them particularly attractive to the plastisol sector, and giving excellent low-temperature flexibility properties. 

Fatty acid esters of short-chain monofunctional alcohols act as secondary plasticizers in PVC. 

Alkyl diaryl and triaryl phosphates have a synergistic action as plasticizers and as flame retardants. Phosphate plasticizers are prepared firom POCI3 and monofunctional alcohols or alkylated phenols. Industrial manufacturing necessitates the manipulation of HCl by-product, which is very corrosive and can cause undesirable side reactions. Because of their flame-retardant properties phosphate plasticizers are employed in fire-retardant apphcations such as cables and spread contract flooring. 

Fatty acid esters, because of the great variety of molecular structures that are possible, offer great versatility to the plastics compounder. Liquid fatty acid esters of short-chain monofunctional alcohols have a distinct secondary plasticizer action, whereas fatty acid esters of long-chain fatty alcohols like stearyl stearate or cetyl palmitate are well known as wax esters and because of their thermal stability, good flow properties and resistance to plate out are broadly used as lubricants for PVC and other polar plastics. 

The composition of hpids on the surface of leaves, stems, and fruits is quite different from that of hpids that form intracellular membranes. Their role is the protection of sensitive plant tissues against the loss of water and other biologically important volatiles. Waxes (i.e., esters of FA with monofunctional alcohols) are the most important components of these lipids. Some plant waxes are of commercial importance, such as camauba or candellila wax. They are solid at room temperature and in temperate climates, with the exception of liquid jojoba wax, and are plastic or even liquid in tropical climates. They contain bound saturated long-chain FA and alcohols. Waxes on the surface of apples and other fruits from temperate zones are solids or semisolid pastes, consisting of terpenes, ceryl cerotate, ceryl palmitate, and other esters. In the wax from lettuce leaves, higher alcohols prevail, with only small amounts of free FA (Bakker et al., 1998). Other components, such as alkanes, ketones, esters, secondary alcohols, were detected in other vegetables (e.g., in kale or rutabaga). 

Monofunctional alcohols may also be cured with epoxyslloxanes, although they act as chain terminators and slow UV cure iSgOH/oxlrane ratios approach 1. This effect is Illustrated for the M N /octanol system in Table VIII below ... 

The alcohol groups can be etherated under these conditions. If monofunctional alcohols are also added (see below), then these nucleophilic substances compete with cross-linking by ether bridges. 

Dimer/trimer acids neutralized with an appropriate amine, such as diethylenetri-amine, have traditionally been employed as components of oil-soluble corrosion inhibitors for reducing corrosion in oil well piping and related recovery equipment in the oil industry. Compositions thereof with monofunctional alcohols and/or polyoxyalkylene glycols are used as grease constituents and industrial lubricants, both in the neat form and, when emulsified, with water. The esters form stable emulsions with water which are useful for working both ferrous and nonferrous metals and in addition impart rust inhibiting properties. 

The Lucas test is used to distinguish between primary, secondary, and tertiary monofunctional alcohols having fewer than six carbon atoms ... 

Figure 4.11 (a) Examples of functional diisocyanates (al, a2), functional monoisocyanates (bl, b2), and monofunctional alcohol (cl) used for polyurethane functionalization before, concurrent, or post polymerization (b) introduction of functional groups into polyurethane through functional diols. 

Low MW glycols such as ethylene glycol, propylene glycol, diethylene glycol and dipropylene glycol are more common polyols, but other dlols such as neopentyl glycol may also be incorporated for superior properties. Monofunctional alcohols are also used as a chain stopper, towards the end of the reaction, to control acid or hydroxyl number. 

There is limited resistance to monofunctional alcohols and glycols. EVM exhibits moderate resistance to mineral oils and fuels. Its resistance is better than that of SBR, but lower than that of NBR. Both swelling and change in mechanical properties depend on the vinyl acetate content. Table 5.ii0. Higher aromatic content in the oil causes more pronounced swelling [697]. Resistance to vegetable and animal oils and fats is also low. 

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