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Updated: Oct 25, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ruthenium(ii)-catalysed 1,2-selective hydroboration of aldazines
Subham Pradhan1, Subramanian Thiyagarajan, Chidambaram Gunanathan
1School of Chemical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar, Khurda-752050, India. gunanathan@niser.ac.in.
Abstract:
Herein, an efficient and simple catalytic method for the selective and partial reduction of aldazines using ruthenium catalyst [Ru(p-cymene)Cl2]2 (1) has been accomplished. Under mild conditions, aldazines undergo the addition of pinacolborane in the presence of a ruthenium catalyst, which delivered N-boryl-N-benzyl hydrazone products. Notably, the reaction is highly selective, and results in exclusive mono-hydroboration and desymmetrization of symmetrical aldazines. Mechanistic studies indicate the involvement of in situ formed intermediate [{(η6-p-cymene)RuCl}2(μ-H-μ-Cl)] (1a) in this selective hydroboration.
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