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In this study, the first highly chemoselective amidation of Boc and amide groups of N -R- N -Boc arylamides is advanced. This practical and operationally-simple method enables the preparation of either N -aroylureas or imides in good to excellent yields without addition of transition metals. The choice of base plays a significant role in controlling the reactivity of the inequivalent carbonyl groups. The amidation of the Boc group was observed with arylamides, ArCONH 2 , when subjected to KO t Bu while imides were produced with LiOH. DFT studies are employed to explore the divergent mechanisms. It is anticipated that these chemoselective methods will be of interest to the synthetic and medicinal chemistry communities.
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Chemoselective acylation of N -acylglutarimides with N -acylpyrroles and aryl esters under transition-metal-free conditions
The imide moiety is a well-known structural motif in bioactive compounds and a useful building block in a variety of processes. Using N -acylglutarimides with MN(SiMe 3 ) 2 and either N -acylpyrroles or aryl esters, an operationally convenient method to produce a wide array of diaryl- and alkyl arylimides is presented. Symmetric imides are also accessible when N -acylglutarimides are employed as acylation reagents under similar reaction conditions. A unique feature of this method stems from the use of two different electrophilic acylating reagents leading to the formation of the unsymmetrical imides with excellent chemoselectivity.
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- Award ID(s):
- 1902509
- PAR ID:
- 10348063
- Date Published:
- Journal Name:
- Organic Chemistry Frontiers
- Volume:
- 8
- Issue:
- 22
- ISSN:
- 2052-4129
- Page Range / eLocation ID:
- 6344 to 6349
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1QO00992C
