A Fluorinated Ligand Enables Room-Temperature and Regioselective Pd-Catalyzed Fluorination of Aryl Triflates and Bromides
摘要:
A new biaryl monophosphine ligand (AlPhos, L1) allows for the room-temperature Pd-catalyzed fluorination of a variety of activated (hetero)aryl trifiates. Furthermore, aryl triflates and bromides that are prone to give mixtures of regioisomeric aryl fluorides with Pd-catalysis can now be converted to the desired aryl fluorides with high regioselectivity. Analysis of the solid-state structures of several Pd(II) complexes, as well as density functional theory (DFT) calculations, shed light on the origin of the enhanced reactivity observed with L1.
A Pd/C-catalyzed deoxygenationmethod of phenolic hydroxyl groups via aryl triflates or mesylates using Mg metal in MeOH at room temperature was developed. The addition of NH4OAc dramatically affects the reactivity and reaction rate. This method is particularly attractive to provide an environmentally benign and widely applicable removal method of phenolic alcohols under quite mild reaction conditions
method for the deoxygenation of phenolic hydroxy groups via aryl triflates or mesylates has been established by using a combination of Pd/C-Mg-MeOH. The addition of NH(4)OAc to the system markedly accelerated the reaction rate and expanded the scope of the reaction. Mechanistic studies suggested that a single-electron transfer process from the Pd(0) center to the benzene ring is involved in the reduction
Formation of ArF from LPdAr(F): Catalytic Conversion of Aryl Triflates to Aryl Fluorides
作者:Donald A. Watson、Mingjuan Su、Georgiy Teverovskiy、Yong Zhang、Jorge García-Fortanet、Tom Kinzel、Stephen L. Buchwald
DOI:10.1126/science.1178239
日期:2009.9.25
currently in use is of great interest. We have prepared [LPd(II)Ar(F)] complexes, where L is a biaryl monophosphine ligand and Ar is an aryl group, and identified conditions under which reductive elimination occurs to form an Ar-F bond. On the basis of these results, we have developed a catalytic process that converts aryl bromides and aryl triflates into the corresponding fluorinated arenes by using simple
Palladium-Catalyzed Synthesis of <i>N</i>,<i>N-</i>Dimethylanilines via Buchwald–Hartwig Amination of (Hetero)aryl Triflates
作者:Tobias Taeufer、Jola Pospech
DOI:10.1021/acs.joc.0c00491
日期:2020.6.5
This work delineates the synthesis of N,N-dimethylaniline derivativesfrom dimethylamines and aryl triflates. The palladium-catalyzedC–Nbond formation proceeds in excellent yields, using an unsophisticated catalytic system, a mild base, and triflates as electrophiles, which are readily available from inexpensive phenols. N,N-Dimethylanilines are multifunctional reaction partners and represent useful
A light-triggered, Ni-catalyzed cyanation of aryl triflates was herein reported, which provides a benign photochemical synthesis of aryl nitriles using 1,4-dicyanobenzene as the CN source instead of HCN or a metallic CN source. This mild method uses a readily available bisphosphine ligand and a soluble organosilicon reagent as the reductant and is carried out under purple light without an external