Palladium-Catalyzed Arylation of Malonates and Cyanoesters Using Sterically Hindered Trialkyl- and Ferrocenyldialkylphosphine Ligands

Abstract

Palladium-catalyzed reactions of aryl bromides and chlorides with two common stabilized carbanions-enolates of dialkyl malonates and alkyl cyanoesters-are reported. An exploration of the scope of these reactions was conducted, and the processes were shown to occur in a general fashion. Using P(t-Bu)(3) (1), the pentaphenylferrocenyl ligand (Ph(5)C(5))Fe(C(5)H(4))P(t-Bu)(2) (2), or the adamantyl ligand (1-Ad)P(t-Bu)(2) (3), reactions of electron-poor and electron-rich, sterically hindered and unhindered aryl bromides and chlorides were shown to react with diethyl malonate, di-tert-butyl malonate, diethyl fluoromalonate, ethyl cyanoacetate, and ethyl phenylcyanoacetate. Although alkyl malonates and ethyl alkylcyanoacetates did not react with aryl halides using these catalysts, the same products were formed conveniently in one pot from diethylmalonate by cross-coupling of an aryl halide in the presence of excess base and subsequent alkylation.

2-Fluoromalonate Esters: Fluoroaliphatic Building Blocks for the Life Sciences

“…57 This methodology has already been employed for the synthesis of novel fluorinated arylamide derivatives that are potential cancer treatment drug candidates. 21a SCHEME 16.…”

Facile Access to Fluoromethylated Arenes by Nickel‐Catalyzed Cross‐Coupling between Arylboronic Acids and Fluoromethyl Bromide

“…To the best of our knowledge,t he nickel-catalyzed direct fluoromethylation of aromatics has not been reported thus far. [7] Ther eported nickel-catalyzed methylations of aromatics are limited by the use of methyl metal reagents (e.g.M eMgX, Me 3 Al, and Me 2 Zn) as coupling partners. [8] This is probably because the most accessible methyl electrophiles (e.g.…”

Palladium‐Catalyzed Carbonylative α‐Arylation for Accessing 1,3‐Diketones

“…Finally, a satisfactory 74 % yield of 22 was obtained in the coupling of 2-tetralone with 2 after treatment of the resulting coupling product with methyl iodide owing to an otherwise a problematic purification. [15] …”