Esterification of Carboxylic Acids and Etherification of Phenols with Amide Acetals

Autor:	Helmut Vorbrüggen
Rok vydání:	2008
Předmět:	Dimethyl acetal chemistry.chemical_compound chemistry Amide Organic Chemistry Iminium Phenol Organic chemistry Methanol Phenols Condensation reaction Tetrahydrofuran
Zdroj:	Synlett. 2008:1603-1617
ISSN:	1437-2096 0936-5214
Popis:	The esterification and etherification of unhindered, as well as severely hindered, carboxylic acids and phenols with basic amide acetals, such as N, N-dimethylformamide dimethyl acetal, and their side reactions are discussed. Modified procedures are described in which these side reactions are avoided to achieve high or near quantitative yields of the desired corresponding methyl esters or phenol methyl ethers. On the addition of N, N-dimethylform-amide dimethyl acetal, solutions of 4-nitrobenzoic acid in basic solvents, such as tetrahydrofuran or 1,4-dioxane, form precipitates of the corresponding iminium carboxylates, which give near quantitative yields of the desired methyl 4-nitrobenzoate, as well as N, N-dimethylformamide and methanol. 1 Introduction 2 Preparation and Properties of Amide Acetals 3 Esterification of Carboxylic Acids and Etherification of Phenols with Amide Acetals 4 Side Reactions during the Esterifications and Etherifications 4.1 Suppression of the Formation of Quaternary Salts and Other Side Reactions 4.2 Tetrahydrofuran or 1,4-Dioxane as Optimal Reaction Solvents 4.3 Attempted Suppression of Condensation Reactions 5 Concluding Remarks
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::1d26b88e81e4365b9984c8c96e440e5d https://doi.org/10.1055/s-2008-1077882 Zobrazit plný text záznamu