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A DFT study on the mechanism of the sulfonic acid + alcohol esterification reaction.

ABSTRACT: Four alternative mechanisms for the benzenesulfonic acid + methanol esterification reaction have been studied at the B3LYP/aug-cc-pVTZ level. The participation of a pentacoordinate sulfur intermediate (in either neutral or protonated form) can be disregarded according to energy considerations. Instead, results show a low activation barrier for the S_N1 pathway (through a sulfonylium cation intermediate) and a moderate barrier for the S_N2 path (involving protonated methanol as an alkylating reagent).

SUBMITTER: Salvatella L

PROVIDER: S-EPMC9077688 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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A DFT study on the mechanism of the sulfonic acid + alcohol esterification reaction.

Salvatella Luis L

RSC advances 20180122 7

Four alternative mechanisms for the benzenesulfonic acid + methanol esterification reaction have been studied at the B3LYP/aug-cc-pVTZ level. The participation of a pentacoordinate sulfur intermediate (in either neutral or protonated form) can be disregarded according to energy considerations. Instead, results show a low activation barrier for the S<sub>N</sub>1 pathway (through a sulfonylium cation intermediate) and a moderate barrier for the S<sub>N</sub>2 path (involving protonated methanol a ...[more]

PMID: 35542947

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