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The iso-Nazarov reaction.

Martín J Riveira¹, Lucía A Marsili, Mirta P Mischne

¹Departamento de Química Orgánica, Instituto de Química Rosario (CONICET - UNR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 - Rosario, Argentina. riveira@iquir-conicet.gov.ar mischne@iquir-conicet.gov.ar.

Organic & Biomolecular Chemistry

|November 1, 2017

Summary

This review explores acid-promoted pentannulation reactions for synthesizing cyclopentenones. These reactions offer a valuable alternative to the Nazarov reaction for creating five-membered rings in organic synthesis.

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Area of Science:

Organic Chemistry
Synthetic Chemistry

Background:

Five-membered ring construction is crucial in organic chemistry.
Cyclopentenones are important structural motifs in natural products and serve as synthetic building blocks.

Purpose of the Study:

To review acid-promoted cycloisomerization reactions of conjugated dienals and linearly-conjugated dienones.
To highlight this method as an alternative to the Nazarov reaction for cyclopentenone synthesis.

Main Methods:

Acid-promoted cycloisomerization of conjugated dienals.
Acid-promoted cycloisomerization of linearly-conjugated dienones.

Main Results:

Demonstration of pentannulation reactions for cyclopentenone synthesis.
Comparison with the well-established Nazarov reaction.

Conclusions:

Acid-promoted cycloisomerization of dienals and dienones is an effective route to cyclopentenones.
This method provides a valuable synthetic strategy, complementing existing reactions.