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Abstract Silyloxyarenes were utilized as electrophilic coupling partners with amines in the synthesis of aniline derivatives. A diverse range of amine substrates were used, including cyclic or acyclic secondary amines, secondary anilines, and sterically hindered primary anilines. Additionally, a range of sterically hindered and unhindered primary aliphatic amines were employed, which have previously been challenging with other classes of aryl ether electrophiles. Orthogonal couplings of silyloxyarenes with aryl methyl ethers are illustrated, where selectivity between the two C−O electrophiles is determined by ligand control, thereby allowing complementary and selective late‐stage diversification of either electrophile. Finally, a sequential coupling displays the utility of this amination method along with the reversal in intrinsic reactivity between aryl methyl ethers and silyloxyarenes.
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An Acid‐Controlled Method for the Regioselective Functionalization of Anilines over Aliphatic Amines
Abstract Regioselective transformations at similar functional groups are of paramount importance in organic synthesis. Traditional strategies towards regioselective functionalization include serial protection/deprotection and sequential synthesis. Modern organic synthesis emphasizes pathway efficiency and protecting group free routes with a goal of exploiting inherent differences in reactivity. This study reports a method for the regioselective functionalization of anilines over aliphatic amines. Utilizing classic conditions for the Baeyer‐Mills reaction, anilines were shown to react preferentially in the presence of aliphatic amines. Subsequently, this principle of reactivity was extended to other electrophiles and conditions.
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- Award ID(s):
- 1904530
- PAR ID:
- 10468092
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 59
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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