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. 2011 Aug 5;76(15):5915-23.
doi: 10.1021/jo201042c. Epub 2011 Jun 27.

Synthesis of substituted pyrazoles via tandem cross-coupling/electrocyclization of enol triflates and diazoacetates

Affiliations

Synthesis of substituted pyrazoles via tandem cross-coupling/electrocyclization of enol triflates and diazoacetates

David J Babinski et al. J Org Chem. .

Abstract

The synthesis of 3,4,5-trisubstituted pyrazoles via a tandem catalytic cross-coupling/electrocyclization of enol triflates and diazoacetates is presented. The initial scope of this methodology is demonstrated on a range of differentially substituted acyclic and cyclic enol triflates as well as an elaborated set of diazoacetates to provide the corresponding pyrazoles with a high degree of structural complexity.

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Figures

Scheme 1
Scheme 1
Pericyclic Approaches to Azoles
Scheme 2
Scheme 2
Electrocyclization Strategies Towards Pyrazoles
Scheme 3
Scheme 3
Unprecedented Rearrangement of 3H-Pyrazoles
Scheme 4
Scheme 4
Diverging Sigmatropic Rearrangements of Propargyl Substituted 3H-Pyrazoles

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References

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