Alcohols, monohydric

Phosgene combines readily with most primary and secondary monohydric alcohols at, or below, ambient temperature to produce high yields of chloroformates (chloromethanoates) according to Equation (10.11)  

OjNC(CH3)jCHj [200] and injCH CHjC hCHj [252]. Polymers containing chloroformate groups have also been prepared by treatment of low molecular weight, CH2CHMeCH(OH)CH3 or (CHj)jCH(OH)CHwith an excess of COCl, [1619]  

Organic carbonates are often formed as by-products in the preparation of chloroformates as a resuit of further reaction between the aicohoi and the chioroformate [1358,2079]  

By using higher temperatures, longer reaction times, and an excess of the aicohoi, the carbonate can be formed in a one-pot reaction according to the stoicheiometry shown in Equation (10.12) [3]  

These reactions are often carried out using dry iiquid alcohois and anhydrous phosgene. Owing to the commerciai importance of both the chioroformates and carbonates (see Section 4.7.2), many exampies are to be found in the patent iiterature which describe other, often obscure or elaborate, means of preparation or production [e.g. 1748,1995]. 

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Monohydric alcohols, aldehydes (including chloral hydrate), ketones, cinnamic acid, amines (2-naphthylaminc is odourless), nitrophenols (resemble both phenol and nitro-compound),... 

If RCOOH is a comparatively simple organic acid and R OH a monohydric alcohol then the enzyme is called an esterase. Examples of such esters are ethyl butyrate, C3H7COOC2H5, and ethyl mandelate, CeHjCH(OH)COOC2Hj. 

Glycols undergo reactions common to monohydric alcohols forming esters, acetals, ethers, and similar products. Eor example, both simple and polyesters are produced by reaction with mono- or dibasic acids (eqs. 1 and 2) ... 

Reactions. Mahc acid undergoes many of the characteristic reactions of dibasic acids, monohydric alcohols, and a-hydroxycarboxyUc acids. When heated to 170—180°C, it decomposes to fumaric acid and maleic anhydride which sublimes on further heating (see Maleic anhydride, maleic acid, AND FUMARIC acid). MaUc acid forms two types of condensation products linear malomalic acids and the cycHc dilactone or maUde it does not form an anhydride. 

Tetrahydronaphthalene [119-64-2] (Tetralin) is a water-white Hquid that is insoluble in water, slightly soluble in methyl alcohol, and completely soluble in other monohydric alcohols, ethyl ether, and most other organic solvents. It is a powerhil solvent for oils, resins, waxes, mbber, asphalt, and aromatic hydrocarbons, eg, naphthalene and anthracene. Its high flash point and low vapor pressure make it usehil in the manufacture of paints, lacquers, and varnishes for cleaning printing ink from rollers and type in the manufacture of shoe creams and floor waxes as a solvent in the textile industry and for the removal of naphthalene deposits in gas-distribution systems (25). The commercial product typically has a tetrahydronaphthalene content of >97 wt%, with some decahydronaphthalene and naphthalene as the principal impurities. 

Uses. Phthabc anhydride is used mainly in plasticizers, unsaturated polyesters, and alkyd resins (qv). PhthaUc plasticizers consume 54% of the phthahc anhydride in the United States (33). The plasticizers (qv) are used mainly with poly(vinyl chloride) to produce flexible sheet such as wallpaper and upholstery fabric from normally rigid polymers. The plasticizers are of two types diesters of the same monohydric alcohol such as dibutyl phthalate, or mixed esters of two monohydric alcohols. The largest-volume plasticizer is di(2-ethylhexyl) phthalate [117-81-7] which is known commercially as dioctyl phthalate (DOP) and is the base to which other plasticizers are compared. The important phthahc acid esters and thek physical properties are Hsted in Table 12. The demand for phthahc acid in plasticizers is naturally tied to the growth of the flexible poly(vinyl chloride) market which is large and has been growing steadily. 

Monohydric Alcohols," in I. MeUan, ed.. Source Book of Industrial Solvents, Vol. 3, Reinhold Publishing Corp., New York, 1959. 

Esterification is one of the most important reactions of fatty acids (25). Several types of esters are produced including those resulting from reaction with monohydric alcohols, polyhydric alcohols, ethylene or propylene oxide, and acetjiene or vinyl acetate. The principal monohydric alcohols used are methyl, ethyl, propyl, isopropyl, butyl, and isobutyl alcohols (26) (see Esterification Esters, organic). 

Ether production from the reaction of monohydric alcohols with linear olefins has also been demonstrated under more severe conditions using a 2eohte-type catalyst system (15). However, it has not been commerciali2ed as yet. 

The various reaction rate properties of the different solvents influence the design of a catalytic reactor. Eor example, for a specific catalyst bed design, an effluent stream containing a preponderance of monohydric alcohols, aromatic hydrocarbons, or propjiene requires a lower catalyst operating temperature than that required for solvents such as isophorone and short-chain acetates. 

Modification of urea-formaldehyde resins with other reagents gives rise to a number of useful materials. For example, co-condensation of urea-formaldehyde and a monohydric alcohol in the presence of small quantities of an acidic catalyst will involve simultaneous etherification and resinification. n-Propanol, n-butanol and isobutanol are commonly used for this purpose. As an example n-butanol will react with the methylol urea as shown in Figure 24.4. 

Epichlorhydrin.—It is a noteworthy fact that althoug-h hydiochloric acid can leplace hydroxyl by chlorine in the case of the monohydric alcohols, the number of hydroxyl groups which are substituted in the case of polyhydric alcohols is strictly limited. Like glyceiol, ethylene glycol gives a chlorhydrin, CIi..OH.CILOII 1- IICl CHnOH.CILCl -1- ILO. 

The reaction of lead tetraacetate (LTA) with monohydric alcohols produces functionalization at a remote site yielding derivatives of tetrahydrofuran (THF) 12). An example is the reaction of 1-pentanol with LTA in nonpolar solvents which produces 30% THF. The reaction, which is believed to proceed through free-radical intermediates, gives a variable distribution of oxidation products depending on solvent polarity, temperature, reaction time, reagent ratios, and potential angle strain in the product. 

An antipolymerization agent such as hydroquinone may be added to the reaction mixture to inhibit the polymerization of the maleate or fumarate compound under the reaction conditions. This reaction is preferably carried out at a temperature within the range of 20°C to 150°C. This reaction is preferably carried out at atmospheric pressure. Reaction time of 16 to 24 hours have bean specified for this reaction by J.T. Cassaday. The reaction is preferably carried out in a solvent such as the low molecular weight aliphatic monohydric alcohols, ketones, aliphatic esters, aromatic hydrocarbons or trialkyl phosphates. 

The results obtained by measuring the affinity to oxygen in the presence of various monohydric alcohols (methanol, ethanol, 2-propanol, 1-propanol) 140-144> were interpreted in terms of the Monod-Wyman-Changeux model145), by which the change of the standard free-energy difference between R and T state in the absence of oxygen, due to the addition of alcohol, can be determined, i.e. 

Studying the reaction of carboxylic oligoesters with monohydric alcohols, Sorokina and Barshtein2231 found the reaction orders 1 and 0.5 with respect to acid and alcohol. However, they did not determine the reaction order relative to catalyst. According to these authors, the most important steps are ... 

Note that all the zero-order rate constants are essentially equivalent except those for the poly-hydric alcohols which are exactly half the value of the others. Ingold et al (Ref 49a) interpret this to mean that the rate of attack of nitronium is the same for both OH groups of the glycol molecule. Since there are two such groups the overall rate constant k0 is Vi that for monohydric alcohols. The explanation for the observed k0 for glycerol is more complex. In essence it consists of postulating that the two outside OH s are readily nitrated, ie, the 1-OH is nitrated at the same rate as the 3-OH, but the middle OH is nitrated much more slowly... 

The choice of the alcohol permits manipulation of the structure of the polymer. Water and monohydric alcohols afford linear chains with carboxylic acid and ester end groups, respectively. Polyhydroxy initiators afford a route to ester end-blocked star and comb polymers (Fig. 4) (47). 

Waxes are esters of fatty acids with alcohols other than glycerol. Most of them are derived from long-chain fatty acids and long-chain monohydric alcohols, both usually having an even number of carbon atoms. Therefore, a wax usually contains an even number of carbon atoms also. 

Solubility soluble in hydrocarbons miscible with water and low molecular weight monohydric alcohols Trochimowicz et al. 1994... 

Linear saturated polyesters of low Molecular weight (less than 10,000) can be obtained by condensing a diol with a diacid. Molecular weight can be controlled by adding a monohydric alcohol or monocarboxylic acid. These polymers are used as plasticisers or as polyester diols for making polyurethanes. 

The grm-diols are considerably stronger acids than the glycols or the monohydric alcohols, and the equilibrium RiR20(0H)2 = RiR20(OH)O -I-H+ can be investigated in alkaline aqueous solutions. 

Monohydric alcohols may be further classified according to the hybridisation of the earbon atom to which the hydrojyl group is attached. 

Addition of Grignard reagents (refer Unit 11, Class XII). Addition of alcohols Aldehydes react with one equivalent of monohydric alcohol in the presence of dry hydrogen chloride to yield alkojyalcohol intermediate, known as hemiacetals, which further react with one more molecule of alcohol to... 

The shape of this wave and the variation with pH are both consistent with fast equ-librium reactions In the pH region lower than the value of pK, for the hydroxyl radical, the reactions of this hydroxyl radical dominate the electrochemical process. Controlled potential reduction at the potential of this first wave indicates a IF process and the principal products are dimers of the hydroxyl radical. The second wave in this acidic region is due to addition of an electron and a proton to the neutral radical. This process competes with dimerization in the mid-pH range where the two polarographic waves merge. Over the pH range 7-9, monohydric alcohol is the principal product. At pH <3 or >12, pinacols are the main products. Unsymmet-rical carbonyl compounds afford mixtures of ( )- and meso-pinacols. Data (Table 10.3) for the ( ) / meso isomer ratio for pinacols from acetophenone and propio-phenone indicate different dimerization mechanisms in acid and in alkaline solutions. 

Cyanoethylation of acrylonitrile with monohydric alcohols gives alkoxypropio-nitriles (Scheme 25). These nitriles can be converted into various types of carboxylic acids by hydrolysis, and they can be hydrogenated to give amines. Therefore, cyanoethylation of alcohols is an important reaction for the synthesis of drug intermediates and organic compounds of industrial interest. 

Other synthetics derived from petroleum, having high viscosity index, low volatility, and low pour point, include polyoxyethylene and polyoxypropylene monohydroxy compounds (22). These can be made by an addition reaction between a monohydric alcohol and an alkylene oxide. 

A drawback for the use of triglycerides and also of fatty acid esters of lower monohydric alcohols as a replacement for diesel fuel alone or in a mixture with diesel fuel has proven to be the flow... 

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