Esters, from carboxylic acids, and

AcCl, MeOH, 95-100% yield. This is a convenient method for generating anhydrous HCl in methanol. These conditions are also used to prepare methyl esters from carboxylic acids and for the formation of amine hydrochlorides. ... 

Other reactions useful for the protection of carboxylic acids are included in Section 107 (Esters from Carboxylic Acids and Acid Halides) and Section 23 (Carboxylic Acids from Esters). 

Esters from carboxylic acids and halides, sulfoxides and miscellaneous compounds... 

Preparation of carboxylic esters from carboxylic acids and alcohols H+ R-C-OH + R OH R-C-OR +H20 II II 0 0... 

Fig. 2.32 Preparation of methyl esters from carboxylic acids and diazomethane.

Esters from Carboxylic Acids and Halides, Sulfoxides, and Miscellaneous compounds. 

Whereas all the alkylations in Figure 2.26 take place in basic or neutral solutions, carboxylic acids can be methylated as such with diazomethane (Figure 2.27). The actual nucleophile (the carboxylate ion) and the actual methylating agent (H3C—N+=N) Fig. 2.27. Preparation of are then produced from the reaction partners by proton transfer, methyl esters from carboxylic acids and di azomethane. 

You can t make esters from carboxylic acids and alcohols under basic conditions because the base deprotonates the carboxylic acid (see p. 288). However, you can reverse that reaction and hydrolyse an ester to a carboxylic acid (more accurately, a carboxylate salt) and an alcohol. 

Esters from carboxylic acids and alcohols under acid catalysis the Aac2 and Ancl mechanism... 

Esters from Carboxylic Acids and Alcohols via Hydroxy Group Activation (HGA)... 

Yokoyama, Y., Shioiri, T., and Yamada, S., Phosphorus in organic synthesis. Part 16. Diphenyl phosphorazidate (DPPA) and diethyl phosphorocyanidate (DEPC). Two new reagents for the preparation of thiol esters from carboxylic acids and thiols, Chem. Pharm. Bull., 25, 2423, 1977. 

Diphenylammonium triflate, toluene, 80°C, 33-97% yield. This catalyst can also be used to prepare esters from carboxylic acids and alcohols, 78-96%... 

In these reactions, hydrolysis of diphenyl and triaryl phosphites to monoaryl phosphites and phenol was coupled by dehydration between carboxylic acids and amines or alcohols to the corresponding amides and esters. Therefore, the reaction can be generalized as a hydrolysis-dehydration reaction (Scheme 2). The concept of the hydrolysis-dehydration reaction using phosphites has been drown to be applicable also to reactions with other phosphorus compounds such as phosphinites, phos-phonites and phosphorates s Aryl esters of these phosphorus compounds are effective as condensing agents in the production of carboxylic amides and esters (from carboxylic acids and amines or alcohols, respectively) whereas alkyl esters are ineffective (Eqs. (1-3)) ... 

The Yamaguchi esterification utilises 2,4,6-trichlorobenzoyl chloride, also known as the Yamaguchi reagent, to form esters from carboxylic acids and alcohols. 

Transesterification. Ethyl esters from carboxylic acids and acetic esters of benzylic alcohols are obtained in the catalyzed transesterification processes, using ethyl acetate as the donor of ethoxy or acetyl group. 

N 0 Me 0 From hydroxymethyl polystyrene by treatment with COClj, HjNNHCOjMe and NBS or Cl,.2i Mitsunobu reactions esters from carboxylic acids and alcohols lactones from hydroxy acids A/-aUcylation of phthalimides, a-alkylation of cyanoacetate carbodiimides from thioureas. ... 

Olofsson and coworkers have developed a general and high-yielding synthesis of various diaryl ethers 681 using the reaction of diaryliodonium salts with phenols under basic conditions (Scheme 3.273) [874]. The scope of products includes bulky orf/io-substituted diaryl ethers, which are difficult to obtain by metal-catalyzed protocols. A similar procedure has been used for the metal-free synthesis of aryl esters from carboxylic acids and diaryliodonium salts [875]. 

Carboxylic acid aryl esters from carboxylic acids and phenols Azeotropic water entrainment... 

Carboxylic acid esters from carboxylic acids and halides COOH -> COOR... 

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