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Abstract Two catalytic systems have been developed for the arylboration of endocyclic enecarbamates to deliver synthetically versatile borylated saturated N‐heterocycles in good regio‐ and diastereoselectivities. A Cu/Pd dual catalytic reaction enables the synthesis of borylated, α‐arylated azetidines, while a Ni‐catalysed arylboration reaction efficiently functionalizes 5‐, 6‐, and 7‐membered enecarbamates. In the case of the Cu/Pd‐system, a remarkable additive effect was identified that allowed for broader scope. The products are synthetically useful, as demonstrated by manipulations of the boronic ester to access biologically active compounds.
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Pd and Fe Cocatalyzed Synthesis of Remotely Borylated Aza-Heterocycles
We report the intramolecular 1,n-aminoboration for the simultaneous synthesis of aza-heterocycles with distal carbon–boron bonds. Pd-catalyzed remote 1,n-aminoboration occurs with 1,2-disubstituted alkenes; upon aminopalladation of the olefin, chain-walking generates the terminal Pd-alkyl intermediate which selectively undergoes Fe-catalyzed borylation. Terminal bishomoallylic amines, amides, carba-mates, and ureas afford the borylated pyrrolidines and lactams through 1,2-aminoboration. Forty-one examples of 1,n-borylated hetero-cycles are presented with yields up to 92% yield. Derivatization of the products is explored: cross-coupling, amination, and oxidation to access unnatural amino alcohols and acids.
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- Award ID(s):
- 2155133
- PAR ID:
- 10650115
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Catalysis
- Volume:
- 14
- Issue:
- 24
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 18507 to 18514
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acscatal.4c05702
