Aliphatic alcohol esters

Solubility and Solvent Resistance. The majority of polycarbonates are prepared in methylene chloride solution. Chloroform, af-l,2-dichloroethylene, X)y 7-tetrachloroethane, and methylene chloride are the preferred solvents for polycarbonates. The polymer is soluble in chlorobenzene or (9-dichlorobenzene when warm, but crystallization may occur at lower temperatures. Methylene chloride is most commonly used because of the high solubility of the polymer (350 g/L at 25°C), and because this solvent has low flammability and toxicity. Nonhalogenated solvents include tetrahydrofuran, dioxane, pyridine, and cresols. Hydrocarbons (qv) and aliphatic alcohols, esters (see Esters, ORGANIC), or ketones (qv) do not dissolve polycarbonates. Acetone (qv) promotes rapid crystallization of the normally amorphous polymer, and causes catastrophic failure of stressed polycarbonate parts. 

Solubility and Solvent Resistance. The majority of polycarbonates are prepared in methylene chloride solution Chloroform, eir-1,2-dichlorocthylcnc, rym-tclrachlorocthanc. and methylene chloride arc the preferred solvents for polycarbonates. Flydrocarbons and aliphatic alcohols, esters, or ketones do not dissolve polycarbonates. Acetone promotes rapid crystallization of the normally amorphous polymer, and causes catastrophic failure of stressed polycarbonate parts. 

Lepidopterous sex pheromones, particularly those produced by female moths, have been primarily determined to be unsaturated normal aliphatic alcohols, esters, or aldehydes (3, 1 , 71). In the present review, emphasis will be placed on the sex pheromones that either are structurally distinctive or representative of the general classes of compounds that are identified with lepidopterous species. Notwithstanding the terminological inexactitude that characterizes the research on lepidopterous exocrine products (72), these compounds will be referred to as sex attractants or pheromones unless otherwise indicated. 

M. Sliwakowski, Ion-trap mass spectra and retention parameters of alkylphosphonic acids low aliphatic alcohols esters, in Proceedings of the 1995 ERDEC Scientific Conference on Chemical and Biological Defense Research, D.A. Berg... 

Organic solvent-soluble components long-chained aliphatic saturated and unsaturated hydrocarbons terpenoid alcohols such as the duvanediols, phytosterols, phytol, and solanesol normal long-chained aliphatic alcohols esters of these groups of alcohols with long-chained aliphatic acids (palmitic, stearic, oleic, etc.)... 

Of the alcoholates, zirconium tetraalcoholates Zr(OR)4 [294], in which the radical R represents an aliphatic or alicyclic radical containing up to 18 carbon atoms, are recommended. Aliphatic alcohols, esters, and alcoholates are used, as a rule, in a mixture with hydrogen chloride acceptors. 

In general the method is more satisfactory with esters of aromatic acids than with esters of aliphatic acids. Esters of alcohols other than methyl and ethyl are best treated by first converting them into methyl esters thus Heat together under reflux i ml. of the higher ester, 5 ml. of methanol and 0-2 g. of sodium methoxide. [In place of the sodium methoxide, it suffices to add o i g. of metallic sodium to the methanol.] After refluxing, distil off the excess of methanol (b.p, 65 ). The residue is then heated under reflux with benzylamine as described above. 

Use of Azeotropes to Remove Water. With the aliphatic alcohols and esters of medium volatility, a variety of azeotropes is encountered on distillation (see Distillation, azeotropic and extractive). Removal of these azeotropes from the esterification reaction mixture drives the equihbrium in favor of the ester product (39). 

Poly(vinyl carbazole) is insoluble in alcohols, esters, ethers, ketones, carbon tetrachloride, aliphatic hydrocarbons and castor oil. It is swollen or dissolved by such agents as aromatic and chlorinated hydrocarbons and tetrahydrofuran. 

For most cases, common fluoroacyl derivatives are sufficiently reactive and selective Thus conversion of perfluoroglutaric dichloride to a monomethyl ester by methanol proceeds smoothly under the appropriate reaction conditions [17] (equation 9) Perfluorosuccinic acid monoester fluoride, on the other hand, is prepared most conveniently from perfluorobutyrolacetone (equation 10) Owing to the strong acidity of a fluorinated carboxylic acids, Fischer esten-ficaiton with most aliphatic alcohols proceeds autocatalytically [79 20]... 

Benzyl alcohol has the piopcities of an aliphatic alcohol, and not those of a phenol. On oxidation, it gives benzaldehyde and benzoic acid, and it foinis benzyl esters with acids or acid chlorides,... 

Tertiary aliphatic alcohols Methyl esters of carboxylic acids Esters of n-chain carboxylic acids Silanes... 

Phenolic compounds are weaker nucleophiles and better leaving groups than aliphatic alcohols. They do not yield polyesters when reacted with carboxylic acids or alkyl carboxy lates. The synthesis of polyesters from diphenols is, therefore, generally carried out through the high-temperature carboxylic acid-aryl acetate or phenyl ester-phenol interchange reactions with efficient removal of reaction by-product (Schemes 2.10 and 2.11, respectively). 

There are many parallels between phosphates and sulfates of aliphatic alcohols. Both types of surfactants contain ester bonds undergoing hydrolysis in acid solutions. In that case the starting materials are received once more. By dry heating of the salts above a temperature of 140°C destruction will occur forming the corresponding alkenes and an inorganic acid salt. In the same way as sulfonic and sulfinic acids are formed by C-S bonds, C-P bonds lead to phosphonic and phosphinic acids. 

Phosphated and Polyphosphated Alcohols In most cases aliphatic alcohols with a chain length in the range of 10-20 carbon atoms are converted with phosphorus pentoxide. A mixture of alkyl dihydrogen esters (primary) and dialkyl hydrogen esters (secondary) are yielded. 

In analytical LC there are two primary reasons why chemical derivatization of the sample constituents would be necessary, and they are 1) to enhance the separation and 2) to increase the sensitivity of detection. Under certain circumstances, derivatization can also be used to reduce peak asymmetry, i.e. to reduce tailing, or to improve the stability of labile components so that they do not re-arrange or decompose during the chromatographic process. However, sensitivity enhancement is the most common goal of derivatization. For example, aliphatic alcohols that contain no UV chromaphore can be reacted with benzoyl chloride to form a benzoic ester. 

This approach has been applied by Rovis and co-workers to the formation of saturated esters from a-haloaldehydes and alcohols. A range of aliphatic alcohols, phenol and aniline proved competent nucleophiles (Scheme 12.17) [30]. 

In the case of an aliphatic alcohol such as iso-octanol, a similar level of defoaming activity together with a much less offensive odour can be achieved by using a propoxylated ester of a branched aliphatic acid, such as propylene-1,2-glycol mononeodecanoate (10.290). 

The repertoire of chemicals that can be used for communication is limited by the biosynthetic ability of the insect. Compared to other insect orders, pheromone biosynthesis in Hymenoptera has received little study [191]. However, the biosynthetic origins of chemically diverse hymenopteran semiochemicals likely include aromatic, fatty acid, and terpenoid pathways as well as simple modifications of host-derived precursors. Notable recent studies include the biosynthesis of the fatty acid components (2 )-9-oxodec-2-enoic acid 52 and (2 )-9-hydroxydec-2-enoic acid of the honeybee queen mandibular pheromone from octadecanoic acid [192,193], and the aliphatic alcohol and ester... 

A sulfonyl chloride group rapidly reacts with amines in the pH range of 9-10 to form stable sulfonamide bonds. Under these conditions, it also may react with tyrosine —OH groups, aliphatic alcohols, thiols, and histidine side chains. Conjugates of sulfonyl chlorides with sulf-hydryls and imidazole rings are unstable, while esters formed with alcohols are subject to nucleophilic displacement (Nillson and Mosbach, 1984 Scouten and Van der Tweel, 1984). The only stable derivative with proteins therefore is the sulfonamide, formed by reaction with e-lysine... 

The reactions of aliphatic alcohols with p-toluenesulfmic acid are accelerated by microwave irradiation under solvent-free conditions in the presence of silica gel, to afford a high-yielding synthesis of p-toluenesulfmate esters [74] (Eq. 21). 

Bashkirov A process for making aliphatic alcohols by oxidizing paraffins. The reaction is conducted in the presence of boric acid, which scavenges the hydroperoxide intermediates. Borate esters of secondary alcohols are formed as intermediates and then hydrolyzed. Developed in the USSR in the 1950s and now operated there and in Japan. 

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