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Updated: May 19, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
One-pot, two-step conversion of aldehydes to phosphonyl- and sulfonylpyrazoles using Bestmann-Ohira reagent
Rahul Kumar1, Deepti Verma, Shaikh M Mobin
1Department of Chemistry, Indian Institute of Technology, Bombay, Mumbai 400 076, India.
Abstract:
A one-pot, two-step, three-component method for the conversion of commercially available aldehydes to phosphonylpyrazoles has been developed, demonstrating, for the first time, the dual reactivity of the Bestmann-Ohira reagent (BOR) in a single-pot transformation. This method, extended to the synthesis of sulfonylpyrazoles by employing BOR in the first step and a diazomethyl sulfone in the second step, is complementary, with regard to regioselectivity, to the previous methods for the synthesis of such functionalized pyrazoles.
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