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The McKenna reaction - avoiding side reactions in phosphonate deprotection.

ABSTRACT: The McKenna reaction is a well-known and popular method for the efficient and mild synthesis of organophosphorus acids. Bromotrimethylsilane (BTMS) is the main reagent in this reaction, which transforms dialkyl phosphonate esters into bis(trimethylsilyl)esters, which are then easily converted into the target acids. However, the versatile character of the McKenna reaction is not always used to its full extent, due to formation of side products. Herein, demonstrated by using model examples we have not only analyzed the typical side processes accompanying the McKenna reaction, but also uncovered new ones. Further, we discovered that some commonly recommended precautions did not always circumvent the side reactions. The proposed results and recommendations may facilitate the synthesis of phosphonic acids.

SUBMITTER: Justyna K

PROVIDER: S-EPMC7323628 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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The McKenna reaction - avoiding side reactions in phosphonate deprotection.

Justyna Katarzyna K Małolepsza Joanna J Kusy Damian D Maniukiewicz Waldemar W Błażewska Katarzyna M KM

Beilstein journal of organic chemistry 20200623

The McKenna reaction is a well-known and popular method for the efficient and mild synthesis of organophosphorus acids. Bromotrimethylsilane (BTMS) is the main reagent in this reaction, which transforms dialkyl phosphonate esters into bis(trimethylsilyl)esters, which are then easily converted into the target acids. However, the versatile character of the McKenna reaction is not always used to its full extent, due to formation of side products. Herein, demonstrated by using model examples we have ...[more]

PMID: 32647545

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