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Alkene isomerization-hydroboration promoted by phosphine-ligated cobalt catalysts
Margaret L Scheuermann1, Elizabeth J Johnson1, Paul J Chirik1
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Abstract:
Generated in situ from air-stable cobalt precursors or readily synthesized using NaHBEt3, (PPh3)3CoH(N2) was found to be an effective catalyst for the hydroboration of alkenes. Unlike previous base-metal catalysts for alkene isomerization-hydroboration which favor the incorporation of boron at terminal positions, (PPh3)3CoH(N2) promotes boron incorporation adjacent to π-systems even in substrates where the alkene is at a remote position, enabling a unique route to 1,1-diboron compounds from α,ω-dienes.
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