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Abstract A method for catalytic intermolecular allylic C−H amination oftrans‐disubstituted olefins is reported. The reaction is efficient for a range of common nitrogen nucleophiles bearing one electron‐withdrawing group, and proceeds under mild reaction conditions. Good levels of regioselectivity are observed for a wide range of electronically diversetrans‐β‐alkyl styrene substrates.
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Sulfenate Anion Catalyzed Diastereoselective Synthesis of Aziridines
Abstract Aziridines are highly valued synthetic targets in organic and medicinal chemistry. The organocatalytic synthesis of such structures with broad substrate scope and good diastereoselectivity, however, is rare. Herein, we report a broadly applicable and diastereoselective synthetic method for the synthesis oftrans‐aziridines from imines and benzylic or alkyl halides utilizing sulfenate anions (PhSO–) as the catalyst. Substrates bearing heterocyclic aromatic groups, alkyl, and electron‐rich and electron‐poor aryl groups were shown to be compatible with this method (33 examples), giving good yields and high diastereoselectivities (trans:cis>20 : 1). Further functionalization of aziridines containing cyclopropyl or cyclobutyl groups was achieved through ring‐opening reactions, with a cyclobutyl‐substituted norephedrine derivative obtained through a four‐step synthesis. We offer a mechanistic proposal involving reversible addition of the deprotonated benzyl sulfoxide to the imine to explain the hightrans‐diastereoselectivity.
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- Award ID(s):
- 2154593
- PAR ID:
- 10418945
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 25
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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