Rapid decarboxylative allylation of nitroalkanes
Alexander J Grenning1, Jon A Tunge
1Department of Chemistry, The University of Kansas, Lawrence, Kansas 66045, USA.
Organic Letters
|January 22, 2010
Summary
Allyl nitroacetates efficiently produce tertiary nitroalkanes via decarboxylative allylation. This rapid, ambient reaction overcomes typical allylation challenges, yielding complex nitroalkanes with high diastereoselectivity.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
Background:
- Decarboxylative allylation is a valuable synthetic transformation.
- Achieving high yields in allylation reactions can be challenging due to competing pathways like O-allylation.
Purpose of the Study:
- To develop an efficient method for synthesizing tertiary nitroalkanes.
- To overcome the limitations of traditional allylation methods, particularly O-allylation.
Main Methods:
- Utilizing allyl nitroacetates as substrates for decarboxylative allylation.
- Employing tandem Knoevenagel/Diels-Alder reactions for substrate preparation.
- Conducting reactions under ambient conditions for several minutes.
Main Results:
- Tertiary nitroalkanes were synthesized in high yields.
- The O-allylation of intermediate nitronates was found to be reversible, contributing to high yields.
- Complex substrates were synthesized and underwent diastereoselective decarboxylative allylation.
Conclusions:
- Decarboxylative allylation of allyl nitroacetates provides a facile route to tertiary nitroalkanes.
- The method is efficient, rapid, and proceeds under mild conditions.
- The strategy allows for the synthesis of complex, stereodefined nitroalkane products.
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