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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
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The McKenna reaction - avoiding side reactions in phosphonate deprotection
Katarzyna Justyna1, Joanna Małolepsza1, Damian Kusy1
1Institute of Organic Chemistry, Faculty of Chemistry, Lodz University of Technology, Zeromskiego St. 116, 90-924 Lodz, Poland.
Beilstein Journal of Organic Chemistry
|July 11, 2020
Summary
The McKenna reaction, using bromotrimethylsilane (BTMS), synthesizes organophosphorus acids but forms side products. This study analyzes known and new side reactions, offering recommendations to improve phosphonic acid synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- The McKenna reaction is a key method for synthesizing organophosphorus acids.
- Bromotrimethylsilane (BTMS) is the primary reagent, converting phosphonate esters to bis(trimethylsilyl)esters.
- Side product formation can limit the reaction's efficiency and scope.
Purpose of the Study:
- To analyze known side processes in the McKenna reaction.
- To identify and characterize novel side reactions.
- To provide recommendations for optimizing phosphonic acid synthesis.
Main Methods:
- Utilized model examples to study reaction pathways.
- Investigated side product formation mechanisms.
- Evaluated the effectiveness of common precautions.
Main Results:
- Identified typical and new side reactions in the McKenna reaction.
- Demonstrated that some standard precautions are ineffective against side reactions.
- Provided insights into factors influencing side product formation.
Conclusions:
- Understanding and mitigating side reactions are crucial for efficient McKenna reactions.
- The findings offer practical guidance for improving phosphonic acid synthesis.
- Further research may refine protocols for cleaner organophosphorus acid production.
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