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Updated: Apr 1, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Catalytic hydroboration of α,β-unsaturated ketones using β-diketiminate magnesium hydride and mechanistic insights
Anubhab Das1, Sayantan Mukhopadhyay1, Sagrika Rajput1
1School of Chemical Sciences, National Institute of Science Education and Research (NISER), Homi Bhabha National Institute (HBNI) Bhubaneswar, 752050, India. snembenna@niser.ac.in.
Abstract:
We report the selective hydroboration of ynones and enones catalyzed by DepNacnac-stabilized magnesium hydride Mg-1 [{LMgH}2; L = DepNacnac = (DepNCMe)2CH; Dep = 2,6-Et2-C6H3] under mild conditions. A wide range of ynones and enones, including testosterone propionate, have been quantitatively converted into the corresponding boronate esters. This magnesium-catalyzed method offers an efficient, eco-friendly alternative to traditional reductions of carbonyl compounds. The active catalyst {LMg-OCH(CH3)CC-Ph}2 (Mg-2) was isolated and characterized via1H, 13C{1H} NMR and single-crystal X-ray diffraction analyses. Based on the isolation of Mg-2 and stoichiometric reactions, a plausible catalytic cycle was established. The results highlight magnesium's potential in sustainable and selective organic transformations.
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