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Abstract Undirected C(sp3)−H functionalization reactions often follow site‐selectivity patterns that mirror the corresponding C−H bond dissociation energies (BDEs). This often results in the functionalization of weaker tertiary C−H bonds in the presence of stronger secondary and primary bonds. An important, contemporary challenge is the development of catalyst systems capable of selectively functionalizing stronger primary and secondary C−H bonds over tertiary and benzylic C−H sites. Herein, we report a Cu catalyst that exhibits a high degree of primary and secondary over tertiary C−H bond selectivity in the amidation of linear and cyclic hydrocarbons with aroyl azides ArC(O)N3. Mechanistic and DFT studies indicate that C−H amidation involves H‐atom abstraction from R‐H substrates by nitrene intermediates [Cu](κ2‐N,O‐NC(O)Ar) to provide carbon‐based radicals R.and copper(II)amide intermediates [CuII]‐NHC(O)Ar that subsequently capture radicals R.to form products R‐NHC(O)Ar. These studies reveal important catalyst features required to achieve primary and secondary C−H amidation selectivity in the absence of directing groups.
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Imino(dialkylamino)isoindolines: Structures and dynamic behavior
In 1956, Elvidge and coworkers investigated the synthesis of a series of isoindoline compounds derived from phthalonitrile. They produced a series of secondary amine-modified isoindolines known as the imino(dialkylamino)isoindolines, and in this report, we revisit this chemistry. In addition to confirming the previously observed reactivity, we structurally characterized three examples and observed a double bond character between the isoindoline carbon atom and the secondary nitrogen atom position. This results in a rotational barrier about this bond, which we observed by NMR spectroscopy and probed using computational methods. The barriers are comparable to those seen in bis-substituted amides.
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- Award ID(s):
- 2153081
- PAR ID:
- 10592816
- Publisher / Repository:
- World Scientific
- Date Published:
- Journal Name:
- Journal of Porphyrins and Phthalocyanines
- Volume:
- 28
- Issue:
- 07
- ISSN:
- 1088-4246
- Page Range / eLocation ID:
- 429 to 434
- 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/10.1142/s1088424624500317
