Aminocarbonylations of alkenyl phosphates, chlorides, bromides, and triflates with Mo(CO)6 as a solid CO source
作者:Olof Lagerlund、Mette L.H. Mantel、Mats Larhed
DOI:10.1016/j.tet.2009.06.101
日期:2009.9
Palladium-catalyzedaminocarbonylations of alkenyl chlorides, bromides, and triflates were investigated using Mo(CO)6 as a solid carbonmonoxidesource. The reactions afforded moderate to good yields producing a wide variety of acrylamides after 20 min of microwave irradiation. In addition, the aminocarbonylationreaction was, for the first time, expanded to include alkenyl phosphates as starting materials
Gold(I)-Catalyzed Stereoselective Synthesis of Alkenyl Phosphates by Hydrophosphoryloxylation
作者:Pierrick Nun、Jonathan D. Egbert、María-José Oliva-Madrid、Steven P. Nolan
DOI:10.1002/chem.201103304
日期:2012.1.23
A pinch of gold will do: Alkenylphosphates, useful substrates in many cross‐coupling reactions, can be synthesized by gold‐catalyzed hydrophosphoryloxylation of terminal alkynes. The use of [Au(IPr)(OH)] as a pre‐catalyst in a silver‐free protocol permits low catalyst loadings and yields excellent results in terms of selectivity toward the kinetic product (see scheme).
Iron-Catalyzed Alkenylation of Grignard Reagents by Enol Phosphates
作者:Gérard Cahiez、Olivier Gager、Vanessa Habiak
DOI:10.1055/s-2008-1067194
日期:2008.8
Stereoselective preparation of trisubstituted olefins can be easily performed from an Z/E-mixture of enol phosphates by reacting only the E-isomer with a Grignardreagent in the presence of Fe(acac) 3 . This procedure combines a kinetic differentiation and a stereoselective reaction. The coupling is very chemoselective in the presence of an alkyl chloride, an ester, a ketone or a nitrile.
A Ligand Free and Room Temperature Protocol for Pd-Catalyzed Kumada−Corriu Couplings of Unactivated Alkenyl Phosphates
作者:Delphine Gauthier、Stephan Beckendorf、Thomas M. Gøgsig、Anders T. Lindhardt、Troels Skrydstrup
DOI:10.1021/jo900098a
日期:2009.5.1
Kumada-Corriu cross-couplings of nonactivated cyclic and acyclic vinyl phosphates with aryl magnesium reagents afforded a series of 1,1-disubtituted alkenes in good yields for most cases when the reactions were performed at room temperature with the simple palladium salt, PdCl2, without the presence of phosphine ligands.
Investigations on the Suzuki−Miyaura and Negishi Couplings with Alkenyl Phosphates: Application to the Synthesis of 1,1-Disubstituted Alkenes
作者:Anders L. Hansen、Jean-Philippe Ebran、Thomas M. Gøgsig、Troels Skrydstrup
DOI:10.1021/jo070912k
日期:2007.8.1
The development of versatile Suzuki-Miyaura and Negishi cross-couplings with nonactivated alkenyl phosphates and aromatic boronic acids or organozinc reagents was achieved in acceptable to good yields. A series of 1,1-disubstituted alkenes were synthesized using a combination of either Ni(COD)(2)/Cy3P/ K3PO4 or Pd(2)dba(3)/DPPF in THF. When working with alkenyl electrophiles in metal-catalyzed cross-couplings, this method lends itself as a less costly and more stable alternative to the corresponding triflate or nonaflate derivatives. In addition, initial studies are presented regarding an efficient 1,2-migration under Negishi coupling conditions.