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Abstract We disclose a Ni‐catalyzed cyclization/alkylmetal interception reaction in which products are readily linearized to permit regiodefined alkene dicarbofunctionalization. This method offers a convenient route to access 1,2‐oxasilolane heterocycles, 3‐hydroxysilanes and 4‐arylalkanols with the formation of C(sp3)−C(sp3) bonds at primary and secondary alkyl carbon centers. In this reaction, a silicon‐oxygen (Si−O) bond functions as a detachable linker that can be delinked with several hydride, alkyl, aryl and vinyl nucleophiles to create profusely functionalized 3‐hydroxysilanes. A silicon motif in the cyclic C(sp3)−Si−O construct in 1,2‐oxasilolane heterocycles can also be selectively deleted by Pd‐catalyzed hydrodesilylation affording Si‐ablated linear alcohol products reminiscent of vicinal ethylene dicarbofunctionalization with C(sp3) and C(sp2) carbon sources.
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Boron insertion into alkyl ether bonds via zinc/nickel tandem catalysis
Mild methods to cleave the carbon-oxygen (C−O) bond in alkyl ethers could simplify chemical syntheses through the elaboration of these robust, readily available precursors. Here we report that dibromoboranes react with alkyl ethers in the presence of a nickel catalyst and zinc reductant to insert boron into the C−O bond. Subsequent reactivity can effect oxygen-to-nitrogen substitution or one-carbon homologation of cyclic ethers and more broadly streamline preparation of bioactive compounds. Mechanistic studies reveal a cleavage-then-rebound pathway via zinc/nickel tandem catalysis.
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- Award ID(s):
- 1654122
- PAR ID:
- 10221102
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 372
- Issue:
- 6538
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- p. 175-182
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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