new and simple one-pot procedure for the palladium-catalyzedintermolecular α-arylation of esters is described. A number of esters can be functionalized with a wide range of aryl bromides using Pd(OAc)2 or Pd2(dba)3 and bulky electron-rich o-biphenyl phosphines 1−3. Under the reaction conditions, using LiHMDS as base, α-arylation proceeds at roomtemperature or at 80 °C with very good yields and high
Efficient Synthesis of α-Aryl Esters by Room-Temperature Palladium-Catalyzed Coupling of Aryl Halides with Ester Enolates
作者:Morten Jørgensen、Sunwoo Lee、Xiaoxiang Liu、Joanna P. Wolkowski、John F. Hartwig
DOI:10.1021/ja027643u
日期:2002.10.1
arylation of alpha,alpha-disubstituted esters were developed with LiNCy(2) as base and P(t-Bu)(3) as ligand. In addition, tert-butyl esters, such as those of Naproxen and Flurbiprofen, were prepared from tert-butyl propionate and aryl bromides in high yields in the presence of Pd(dba)(2) and the hindered, saturatedheterocycliccarbene ligand precursor.
α-Arylation of Esters Catalyzed by the Pd(I) Dimer {[P(<i>t-</i>Bu)<sub>3</sub>]PdBr}<sub>2</sub>
作者:Takuo Hama、John F. Hartwig
DOI:10.1021/ol8002578
日期:2008.4.1
Conditions for the coupling of bromoarenes with esters using a single base and catalyst with improved turnovernumbers are described. These general conditions were made possible by using the Pd(I) catalyst [P(t-Bu)3]PdBr}2. Reactions of acetates, propionates, and isobutyrates are presented, and reactions of all three classes of esters on a 10 g scale are described.
Cu(I)/Chiral Bisoxazoline‐Catalyzed Enantioselective Doyle‐Kirmse Reaction of Allenyl Sulfides with
<i>α</i>
‐Diazoesters
作者:Kang Wang、Shu‐Sen Li、Jianbo Wang
DOI:10.1002/chem.202200170
日期:2022.4.12
A Cu(I)/chiral bisoxazoline-catalyzed enantioselective Doyle-Kirmse reaction of polyfluoroaryl allenylsulfides with α-diazoesters, generating chiral tertiary homopropargylic sulfides in good enantioselectivities under mild conditions.
Catalytic Asymmetric Syntheses of Alkylidenecyclopropanes from Allenoates with Donor‐Acceptor and Diacceptor Diazo Reagents
作者:Yoko Hasegawa、Thomas Cantin、Jonathan Decaens、Samuel Couve‐Bonnaire、André B. Charette、Thomas Poisson、Philippe Jubault
DOI:10.1002/chem.202201438
日期:2022.8.22
Chiral ACPs: The catalytic asymmetric synthesis of alkylidenecyclopropanes from electron-deficient allenes is described. The methodology, using donor-acceptor or diacceptor diazo reagents, catalyzed by a chiral rhodium complex furnished the corresponding ACPs in high yields with excellent diastereo- and enantioselectivities.