Esters synthesis from

Solutions of dinitrogen pentoxide in anhydrous nitric acid are unlikely to find wide use for the industrial synthesis of nitrate esters - synthesis from the parent alcohol is relatively straightforward and so this reagent, which is more expensive than mixed acid, holds few advantages. 

The general method for ester synthesis from an alcohol and an acid chloride. 

Methylheptanoic acid has been prepared by mixed electrolysis of / -methylglutaric acid monomethyl ester and butyric acid, followed by saponification of the methyl ester,10 and by the mal-onic ester synthesis from 2-bromohexane.11 The present method7 has the advantage of avoiding the use of secondary bromides, which are often difficult to secure entirely pure.12... 

Ikushima et al. (1996) Batch Ester synthesis from acyl donors and terpene alcohols Lipase from Candida cylindracea... 

Scheme 1.3 Pracejus enantioselective ester synthesis from phenyl methyl ketene.

Under almost anhydrous conditions in organic medium, lipases can be used in the reverse mode for direct ester synthesis from carboxylic acids and alcohols, as well as transesterifications (acyl transfer reactions) which can be divided into alcoholysis (ester and alcohol), acidolysis (ester and acid), and interesterification (ester-ester interchange). The direct esterification and alcoholysis in particular have been most frequently used in asymmetric transformations involving lipases. The parameters that influence enzymatic catalysis in organic solvents have been intensively studied and discussed. ... 

The mechanism of ester hydrolysis in acid (shown in Mechanism 22.8) is the reverse of the mechanism of ester synthesis from carboxylic acids (Mechanism 22.6). Thus, the mechanism consists of the addition of the nucleophile and the elimination of the leaving group, the two steps common to all nucleophilic acyl substitutions, as well as several proton transfers, because the reaction is acid-catalyzed. 

Tridecylic acid has been prepared by the malonic ester synthesis from undecyl iodide,1 by the oxidation of a-hydroxymyristic acid in acetone with potassium permanganate,2 by the action of dodecyl bromide on potassium cyanide and subsequent hydrolysis,3 and from undecyl iodide and ethyl cyanoacetate.4 The present method is an adaptation of that of Ruzicka, Stoll, and Schinz.3... 

Gerlach and Wetter (11) achieved rather better levels of control, also using catalytic hydrogenation for the relative stereochemistry between C-3 and C-6 (Scheme 3). 2-Furylacetone 25 was prepared by a Darzens glycidic ester synthesis from furfural, and was functionalised at the 5-position using Eschenmoser s 2-chloro-Af-cyclohexyl-propionaldonitrone 26 in the presence of... 

Mazzocchia, C. G. Modica A. Kaddouri R. Nannicini. Fatty acid methyl esters synthesis from triglycerides over heterogeneous catalysts in the presence of microwaves. C.R Chimie 2004, 7, 601-605. 

Displayed here is a general mechanism for acetoacetic ester synthesis from th... 

In every synthetic reaction where a net amount of water is formed (such as an ester synthesis from an alcohol and a carboxylic acid [38 0]) physicochemical problems arise. Due to the fact that the lipophilic solvent (log F > 1.5) is unable to accommodate the water which is gradually produced during the course of the reaction, it is collected at the hydrophilic enzyme surface. As a consequence, the water gradually forms a discrete aqueous phase which encompasses the enzyme, finally separating substrate and enzyme from each other by a polar interface, which is difficult to penetrate for lipophilic substrate/product molecules. Thus, the rate... 

Acrylic ester synthesis from acetylene, carbon monoxide, and alcohols with the aid of nickel carbonyl is known as the Reppe synthesis and is very important in industrial applications (Reppe, 1953). This carboxylation re-... 

Ruthenium and ruthenium compounds are mainly used as hydrogenation catalysts and oxidation catalysts, e.g., catalysts for the hydrogenation reaction of carbon monoxide and aromatic compounds, aldehyde synthesis by fission of a carbon-carbon double bond, from alcohols to aldehydes or ketones, aldehydes to carboxylic acids, and ester synthesis from ether [5—7]. 

If the same reaction is carried out at temperatures between 250-270 °C and slightly increased CO-partial pressure, succinic acid is obtained as the main product [384]. High acetylene partial pressure in the acrylic ester synthesis from acetylene, carbon monoxide and alcohol in the presence of... 

The selection of the catalyst system will often be determined by the process technique used. In the catalytic processing of acrylic acid-n-butyl ester synthesis from acetylene, carbon monoxide and n-butanol with nickel halogenide, troublefree continuous operation could not be achieved. 

Table 3. Enantiomer-Selective Ester Synthesis from Acid Salts and Alkyl Bromides in the Presence of Optically Active Pol3oners at 80 C in Benzene... 

Ester Synthesis from Carboxylic Acids Through Acyl Chlorides... 

Formation of Carboxylic Esters and Ketones, Grignard reagents can also be converted into esters and ketones by Fe(CO)5 (to supply CO). A cathodic ester synthesis from alcohols and alkyl halides uses carbon monoxide (at 1 atm) and Fe(CO)s as a catalyst. ... 

Ester synthesis from 1-pentanol and 2-, 3-, or 4-methylpentanoic acid was also investigated with these PEG-lipases [81]. Although PEG-lipase from P. fluorescens could only catalyze the esterification of 4-methylpentanoic acid with 1-pentanol as shown in Table 10, PEG-lipase from C. cylindracea catalyzed the esterification of these substituted carboxylic acids with I-pentanol. In particular, esterification of 2-methylpentanoic acid... 

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