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Updated: Aug 24, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Stereocontrolled entry to borylated piperidines via stepwise dearomative carboboration of pyridines
Laxman D Khalse1, William DeSnoo2, Yin-Peng Lou1
1Institute of Chemistry, Casali Center of Applied Chemistry, The Hebrew University of Jerusalem Jerusalem 9190401 Israel z.nairoukh@mail.huji.ac.il.
Abstract:
We disclose a stepwise dearomative carboboration that converts pyridine precursors into substituted borylated piperidines with excellent site-, regio-, and diastereocontrol. In this strategy, pyridines are first converted to 1,2-dihydropyridines by regioselective nucleophilic dearomatization, and the resulting dihydropyridines undergo Pd-catalyzed carboboration with diverse alkenyl triflates and diboron reagents. Computational analysis supports a non-classical activation mode of diboron that involves oxidative addition to palladium to access a transient Pd(iv) intermediate and identifies the features that control selectivity. Downstream derivatizations of the boronate handle highlight the synthetic versatility of the products.
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