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Abstract A nickel‐catalyzed conjunctive cross‐coupling of alkenyl carboxylic acids, aryl iodides, and aryl/alkenyl boronic esters is reported. The reaction delivers the desired 1,2‐diarylated and 1,2‐arylalkenylated products with excellent regiocontrol. To demonstrate the synthetic utility of the method, a representative product is prepared on gram scale and then diversified to eight 1,2,3‐trifunctionalized building blocks using two‐electron and one‐electron logic. Using this method, three routes toward bioactive molecules are improved in terms of yield and/or step count. This method represents the first example of catalytic 1,2‐diarylation of an alkene directed by a native carboxylate group.
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This content will become publicly available on August 15, 2026
Palladium-Catalyzed Aerobic Alkene Arylboration: Coupling Aryl Boronic Acids, Alkenes, and Bis(pinacol)diboron
Alkyl boronic acids and esters are versatile synthetic intermediates that generally require several steps to synthesize. Three-component alkene arylboration reactions allow for the rapid synthesis of alkyl boronic esters. Herein, we report the base-free aerobic Pd-catalyzed three-component alkene arylboration, which allows direct access, in a single step, to alkyl boronic esters from readily available precursors: aryl boronic acids, alkenes, and bis(pinacol)diboron. This approach allows for the formal insertion of an alkene into an Ar–B bond, and thus, generates an alkyl boronic ester from an aryl boronic acid. The reaction proceeds with both electron-rich and electron-deficient aryl boronic acids as well as strained cyclic, internal, and terminal olefins. The reactions are regioselective: 1,2-arylboration products are formed with strained cyclic alkenes and b-alkyl-styrenes while 1,1-arylboration products are generated from terminal alkenes. Forty-five examples are presented with isolated yields of the resulting alkyl boronic esters ranging from 20-74%, along with several examples demonstrating the synthetic utility of the products. Mechanistic investigations support that the catalytic cycle occurs through direct arylboration of the alkene. Further, p-benzyl intermediates form when possible, and the rate of borylation is increased with electron-rich arenes relative to electron-poor. Finally, we demonstrate that aryl boroxines, generated in situ, are essential for the transformation as they rapidly undergo base-free transmetalation with the proposed palladium peroxo intermediate.
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- Award ID(s):
- 2155133
- PAR ID:
- 10650114
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Catalysis
- Volume:
- 15
- Issue:
- 16
- ISSN:
- 2155-5435
- Page Range / eLocation ID:
- 14564 to 14574
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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