Carbene Bridging C-H Activation: Facile Isocoumarin Synthesis Through Palladium-Catalyzed Reaction of 2-Pseudohalobenzaldehydes with Aryl Diazoesters
作者:Chao Yan、Yinghua Yu、Bo Peng、Xueliang Huang
DOI:10.1002/ejoc.201901738
日期:2020.2.14
A strategy based on carbene bridging C–H activation is described. The bridging arm is generated via migratory insertion of a palladium carbene intermediate. Through this distinct pathway, a variety of isocoumarins could be prepared in a modular manner.
Palladium‐Catalyzed Chemoselective Borylation of (Poly)halogenated Aryl Triflates and Their Application in Consecutive Reactions
作者:Shan Shan Ng、Zicong Chen、On Ying Yuen、Chau Ming So
DOI:10.1002/adsc.202101501
日期:2022.4.26
This study reports the palladium-catalyzed chemoselective borylation of (poly)halogenated aryl triflates with a reactivity order of C−Cl>C−OTf. A catalyst system comprising Pd(OAc)2 and SelectPhos (L1) enables a reaction with high reactivity and chemoselectivity. The consecutively chemoselective borylation reaction followed by the chemoselective intermolecular Suzuki-Miyaura reaction can be performed
A ligand-controlled palladium-catalyzed three-component reaction of o-bromobenzaldehyde, N-tosylhydrazone, and methanol is described. This reaction uses readily available compounds as starting materials while displaying a broad substrate scope and good functional group compatibility.
Triflate‐Selective Suzuki Cross‐Coupling of Chloro‐ and Bromoaryl Triflates Under Ligand‐Free Conditions
作者:Grace M. Ibsen、Vitor H. Menezes da Silva、J. Cole Pettigrew、Sharon R. Neufeldt
DOI:10.1002/asia.202300036
日期:——
“Ligand-free” room-temperature conditions for Pd-catalyzed Suzuki couplings of haloaryl triflates give selectivity for triflate over chloride or bromide. For chloroaryl triflates, triflate selectivity is exclusive and represents an improvement over conditions with strong ancillary ligands. The triflate selectivity with bromoaryl triflates is unprecedented for Suzuki couplings. Solvent choice is critical