Esterifications alcohols

Oxalic acid produced from syngas can be esteiified (eq. 20) and reduced with hydrogen to form ethylene glycol with recovery of the esterification alcohol (eq. 21). Hydrogenation requires a copper catalyst giving 100% conversion with selectivities to ethylene glycol of 95% (15). 

Lipases play an important role in organic synthesis and also in flavour biotechnology. Pig pancreatic extract and especially many microbial lipases are used for ester hydrolysis, esterification (alcohol and acid), transesterification (ester and... 

Although zwitterions are mainly considered for their novel ion conductive matrix in this chapter, they are being used as not only as solvents and catalysts for organic reactions [42] but also as organogelators [43]. Zwitterions have been screened as solvent/catalysts for several classical acid-promoted organic reactions such as the Fischer esterification, alcohol dehydrodimerization, and the pinacol/ benzopinacole rearrangement. The zwitterion containing an equimolar trifluoro-methane sulfonic acid is liquid at room temperature. Because they can work as solvent/catalysts, as shown in the reactions discussed in this chapter, zwitterionic liquids should open the door to a whole new area of applications. 

Trans) esterification Alcohol/carboxylic acid/carboxylic ester... 

It is used as a catalyst in esterification, dehydration, polymerization and alkylation reactions. Converted by e.g., ihionyl chloride, to melhanesulphonyl chloride (mesyl chloride) which is useful for characterizing alcohols, amines, etc. as melhanesulphonyl (mesyl) derivatives. 

The mechanism of esterification of an alcohol in the presence of a mineral acid is now considered to involve the following steps. 

The oxidation with excess of dichromate and dilute sulphuric acid is not always satisfactory for alcohols higher than n propyl because of the attendant production of appreciable amounts of esters indeed by using a fairly high concentration of sulphuric add, good yields of esters are obtained since esterification takes place at once, even in the cold, as long as an excess of alcohol is present, for example ... 

Esterification with cycloaliphatic alcohols is comparatively easy when the alcohol is saturated with hydrogen chloride and treated with excess of the acid, but a very impure ester results from the use of sulphuric acid as a catalyst, for example ... 

The benzene - alcohol method is useful for the esterification of valuable monobasic acids, but the b.p. of the ester must be at least 50° higher than that of benzene, for example ... 

The distillate contains alcohol, toluene and water, and may be dried with anhydrous potassium carbonate and used again for esterification after the addition of the necessary quantity of alcohol alternatively, the toluene may be recovered by washing with water, drying with anhydrous calcium chloride or anhydrous magnesium sulphate, and distiUing. 

Esterification with an aromatic alcohol may be readily achieved by using an excess of the acid. The latter is readily removed by washing with water and/or treatment with sodium bicarbonate solution, for example ... 

From the nitrile. By refluxing a mixture of the aromatie nitrile (with —CN group in aide chain) with alcohol and concentrated sulphuric acid simultaneous hydrolysis and esterification occurs, for example ... 

Ethyl p-aminobenzoate (esterification of p-aminobenzoic acid). Place 80 ml. of absolute ethyl alcohol in a 250 ml. conical flask equipped with a two-holed cork and wash-bottle tubes. Pass dry hydrogen chloride (Section 11,48,2) through the alcohol until saturated—the increase in weight is about 20 g.—and transfer the solution to a 250 ml. round-bottomed flask. Introduce 12 g. of p-aminobenzoic acid, fit a double surface condenser to the flask, and reflux the mixture for 2 hours. Upon... 

Usually no difficulties are encountered in the esterification of thiazole acids. Direct esterification with alcohol and add in the presence of an acid catalyst (7, 61, 62), or prior conversion to the add chloride (6, 63, 64) followed by reaction with an alcohol in basic conditions give good yields. 

Acid catalyzed condensation of an alcohol and a carboxylic acid yields an ester and water and IS known as the Fischer esterification... 

Fischer esterification is reversible and the position of equilibrium lies slightly to the side of products when the reactants are simple alcohols and carboxylic acids When the Fis cher esterification is used for preparative purposes the position of equilibrium can be made more favorable by using either the alcohol or the carboxylic acid m excess In the following example m which an excess of the alcohol was employed the yield indicated IS based on the carboxylic acid as the limiting reactant... 

For steric reasons the order of alcohol reactivity m the Fischer esterification is CH3OH > primary > secondary > tertiary... 

The mechanisms of the Fischer esterification and the reactions of alcohols with acyl chlorides and acid anhydrides will be discussed m detail m Chapters 19 and 20 after some fundamental principles of carbonyl group reactivity have been developed For the present it is sufficient to point out that most of the reactions that convert alcohols to esters leave the C—O bond of the alcohol intact... 

The acyl group of the carboxylic acid acyl chloride or acid anhydride is trans ferred to the oxygen of the alcohol This fact is most clearly evident m the esterification of chiral alcohols where because none of the bonds to the chirality center is broken m the process retention of configuration is observed... 

Although the term ester used without a modifier is normally taken to mean an ester of a carboxylic acid alcohols can react with inorganic acids m a process similar to the Fis cher esterification The products are esters of inorganic acids For example alkyl nitrates are esters formed by the reaction of alcohols with nitric acid... 

Esterification with acyl chlorides (Section 15 8) Acyl chlorides react with alcohols to give esters The reaction is usually carried out in the presence of pyridine... 

Esterification (Section 15 8) In the pres ence of an acid catalyst carboxylic acids and alcohols react to form esters The reac tion IS an equilibrium process but can be driven to favor the ester by removing the water that is formed... 

The answer to this question is critical because it tells us whether the carbon-oxygen bond of the alcohol or a carbon-oxygen of the carboxylic acid is broken during esterification... 

Fingerprint region (Section 13 20) The region 1400-625 cm of an infrared spectrum This region is less character istic of functional groups than others but varies so much from one molecule to another that it can be used to deter mine whether two substances are identical or not Fischer esterification (Sections 15 8 and 19 14) Acid cat alyzed ester formation between an alcohol and a carboxylic acid... 

AH the common monobasic (107) and dibasic esters (108) of tetrahydrofurfuryl alcohol have been prepared by conventional techniques the dibasic esters and some of the mono esters are effective as primary or secondary plasticizers for vinyl polymers. Tetrahydrofurfuryl acrylate [2399-48-6] and methacrjiate [2455-24-5] specialty monomers, have been produced by carbonylation (nickel carbonyl and acetylene) of the alcohol (109) as weU as by direct esterification (110—112) and ester interchange (111). 

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