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  • Controlling Catalyst Speciation to Achieve Room Temperature Pd‐Catalyzed Aminations with Aryl and Heteroaryl Chlorides

This content will become publicly available on January 15, 2026

Title: Controlling Catalyst Speciation to Achieve Room Temperature Pd‐Catalyzed Aminations with Aryl and Heteroaryl Chlorides
Abstract The amination of aryl halides with palladium catalysts (Buchwald‐Hartwig amination) is a widely used transformation in synthetic and drug discovery chemistry. In this report, we demonstrate that a monometallic 2‐phosphinoimidazole Pd catalyst exhibits comparable or enhanced reactivity when compared to all ligands screened for room temperature amination of aryl chlorides with secondary amines. The di‐tert‐butylphosphine derivative showed extremely high reactivity while the di‐isopropyl variant led to almost complete loss of catalytic activity. Computational and experimental mechanistic and kinetic studies indicate that a monometallic Pd structure rather than a bimetallic Pd structure is key to fast catalysis. The di‐tert‐butylphosphine ligand has fast catalysis because it thermodynamically disfavors the formation of a much less active bimetallic Pd complex. A wide substrate scope is demonstrated for the arylation of secondary amines with aryl chlorides using our new catalyst system.  more » « less
Award ID(s):
2153215
PAR ID:
10569262
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Synthesis & Catalysis
ISSN:
1615-4150
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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