Highly Selective Nickel‐Catalyzed Isomerization‐Hydroboration of Alkenes Affords Terminal Functionalization at Remote C‐H Position
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Published:2023-07-19
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Volume:
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ISSN:0947-6539
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Container-title:Chemistry – A European Journal
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language:en
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Short-container-title:Chemistry A European J
Author:
Saunders Tyler M.1,
Shepard Sydney B.1,
Hale Dylan J.1,
Robertson Katherine N.2,
Turculet Laura3
Affiliation:
1. Dalhousie University Department of Chemistry CANADA
2. Saint Mary's University Department of Chemistry CANADA
3. Dalhousie University Department of Chemistry 6274 Coburg Rd. PO Box 15000 B3H 4R2 Halifax CANADA
Abstract
We report herein the synthesis and characterization of nickel complexes supported by tridentate and bidentate phosphino(silyl) ancillary ligands, along with the successful application of these complexes as precatalysts for the hydroboration of terminal and internal alkenes using pinacolborane (HBPin). These reactions proceeded with low nickel loadings of 2.5‐5 mol % in the absence of co‐solvent, and in some cases at room temperature. Isomerization to afford exclusively the terminal hydroboration product was obtained across a range of internal alkenes, including tri‐ and tetra‐substituted examples. This reactivity is unprecedented for nickel and offers a powerful means of achieving functionalization at a C‐H position remote from the C=C double bond. Nickel‐catalyzed deuteroboration experiments using DBPin support a mechanism involving 1,2‐insertion of the alkene and subsequent chain‐walking, which results in isotopic scrambling.
Subject
General Chemistry,Catalysis,Organic Chemistry