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Abstract Strained rings are increasingly important for the design of pharmaceutical candidates, but cross‐coupling of strained rings remains challenging. An attractive, but underdeveloped, approach to diverse functionalized carbocyclic and heterocyclic frameworks containing all‐carbon quaternary centers is the coupling of abundant strained‐ring carboxylic acids with abundant aryl halides. Herein we disclose the development of a nickel‐catalyzed cross‐electrophile approach that couples a variety of strained ringN‐hydroxyphthalimide (NHP) esters, derived from the carboxylic acid in one step, with various aryl and heteroaryl halides under reductive conditions. The chemistry is enabled by the discovery of methods to control NHP ester reactivity, by tuning the solvent or using modified NHP esters, and the discovery thatt‐BuBpyCamCN, an L2X ligand, avoids problematic side reactions. This method can be run in flow and in 96‐well plates.
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This content will become publicly available on August 15, 2026
Synthesis of a highly strained deep cavitand
Access to highly strained molecules remains a challenge. We report the synthesis of a bench-stable and highly strained (∼135 kcal mol−1) deep cavitand.
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- Award ID(s):
- 2302628
- PAR ID:
- 10630528
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Communications
- ISSN:
- 1359-7345
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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